devpack Features — Every Free Developer Tool and What It Does

HTML & CSS to Webflow

Convert HTML and CSS into native Webflow elements with classes, combo classes, breakpoints and hover states, then paste straight into the Designer. Free.

• AI-generated sections — ask ChatGPT or Claude for a section in HTML and CSS with class names, then paste it here instead of rebuilding it by hand.
• Templates and UI kits — HTML/CSS templates or exported prototypes.
• Tailwind — Tailwind utility classes don’t translate well to Webflow classes; compile to plain CSS with semantic class names first, or let the Class Name…

SVG to Webflow

Convert an SVG into native Webflow Custom Elements (svg, path, g…) with all attributes and paste it straight into the Designer — or as a Code Embed.

Markdown to Webflow Rich Text

Convert Markdown (from ChatGPT, Claude, Notion or GitHub) into formatted rich text you can paste straight into Webflow’s Rich Text element or CMS fields. Free.

Class Name Generator

Describe a section and get a clean class structure in Client-First, BEM or kebab-case — with HTML skeleton, starter CSS and one-click copy to Webflow.

Figma CSS to Webflow

Paste CSS copied from Figma Dev Mode and get clean Webflow-ready values: rem units, unitless line-height, em letter-spacing, grouped by Style panel section.

Class Name Typo Checker

Find typos, near-duplicates, mixed separators and unnamed Webflow classes like div-block-12. Check a live URL or pasted HTML, with Client-First and BEM rules.

• Rename — a class by selecting an element that uses it, then double-clicking the class in the Selector field — all elements using it update.
• Merge a typo — into the correct class by selecting the elements with the typo, removing it and applying the right class; then delete the unused class with Style…

Webflow Clipboard Bridge

Copied Webflow elements won’t paste in another browser? Paste them here, inspect or edit the clipboard JSON, and copy again so the Designer accepts them.

• Same browser, same clipboard — if devpack and Webflow are open in the same browser, you don’t need the bridge — paste straight into the Designer.
• Between Webflow projects — copying elements between sites works in one browser too; classes are recreated, and images are re-linked from the original site’s assets.
• Save components for later — download the JSON and reopen it any time — a lightweight snippet library for sections you reuse.

HTML to Webflow Rich Text

Strip classes, inline styles, divs and spans from HTML (or content pasted from Google Docs/Word) so it imports cleanly into Webflow Rich Text and CMS fields.

Lottie JSON Optimizer

Shrink Lottie JSON animations for Webflow and websites: round numbers, strip layer names, metadata and hidden layers. See size savings instantly — runs locally.

SEO Checker & Site AuditNeeds internet

Free website audit: 70 on-page SEO checks plus speed, security headers, SSL, schema, broken links, AI crawlers, tracking and email DNS — with one site score.

Broken Link CheckerNeeds internet

Free online broken link checker: scan any page for dead links, 404 errors, redirects and bot-blocked URLs. Live results, anchor text and CSV export.

• Internal 404s — correct the link, or if the target page moved, add a 301 redirect from the old URL (our Redirect Generator writes the rules for Apache, Nginx and…
• External 404s — find the new location of the resource, link to an archived copy, or remove the link.
• Redirected links — replace them with the final URL shown in the results. Use the Redirect Checker to inspect long chains.

Schema Markup Generator

Generate valid JSON-LD schema markup for Organization, LocalBusiness, Article, FAQ, Product, Event, JobPosting and more. Free, with Google field checks.

• Mark up what is visible — Ratings, prices and FAQ answers must also appear on the page. Self-serving reviews of your own business are not eligible for review stars.
• Use absolute URLs and ISO 8601 — URLs need https://; dates look like 2026-10-25 or 2026-10-25T19:30:00+01:00; durations look like PT1H30M.
• One entity, one block — Several JSON-LD blocks per page are fine (for example Organization plus BreadcrumbList); don’t mix the same entity across formats.

Meta Tag Generator

Generate SEO meta tags, Open Graph and Twitter card tags, canonical, robots and favicon links with live Google, Facebook and X previews. Free online.

• Relative og:image URLs — Social scrapers need an absolute https:// URL. Add og:image:width and og:image:height so the image renders on the very first share instead of after a…
• Noindex plus canonical — Pointing a canonical at another URL while also setting noindex sends mixed signals; pick one.
• Unescaped quotes — A " inside a description breaks the attribute. All values are HTML-escaped in the output.

Tracking & Pixel CheckerNeeds internet

See every tracking tag on a website: Google Analytics 4, Tag Manager, Google Ads, Meta Pixel, LinkedIn, TikTok, Hotjar, consent tools and Search Console tags.

• Universal Analytics leftovers — UA stopped processing data in 2023 (2024 for GA360). Remove UA- snippets; they only slow the page.
• Double GA4 — the same G- ID hard-coded in the site and fired by GTM inflates page views and halves bounce rates.
• Pixels without consent — in the EU/UK, analytics and ad pixels generally require prior consent. Load them through your consent tool or GTM consent triggers.

Page Speed TestNeeds internet

Free page speed test powered by Google Lighthouse. Check Core Web Vitals (LCP, CLS, INP), performance scores and the top fixes for mobile and desktop.

• LCP — compress and correctly size the hero image (try the Image Compressor), serve WebP/AVIF, don't lazy-load it, and reduce server response time.
• TBT / INP — remove unused JavaScript and heavy third-party tags, defer non-critical scripts, and break up long tasks.
• CLS — set width and height on images and embeds, reserve space for ads and cookie banners, and use font-display with matched fallback fonts.

Sitemap GeneratorNeeds internet

Generate an XML sitemap free by crawling your site: only indexable, canonical pages that return 200 are included, with optional lastmod. Download sitemap.xml.

Robots.txt Generator

Create a robots.txt file with per-bot rules, presets to block AI training crawlers like GPTBot and ClaudeBot, sitemap links and syntax warnings. Free.

• Using robots.txt to de-index pages — A blocked URL can still be indexed (without a snippet) if other sites link to it. Use a noindex meta tag — and don’t block that page, or Google can’t…
• Blocking CSS and JavaScript — Google renders pages; blocking /assets/ or /wp-includes/ can make pages look broken to it.
• Relying on Crawl-delay — Bing and Yandex respect it; Googlebot ignores it.

robots.txt Explainer

Paste or fetch a robots.txt and see each rule explained in plain English per crawler — wildcards, Allow vs Disallow precedence, crawl-delay and common mistakes.

• Pick a group — a crawler uses the group whose User-agent matches its name most specifically, and only that group. Googlebot ignores the * group if a Googlebot group…
• Find matching rules — Disallow and Allow values are path prefixes. * matches any characters, $ marks the end of the URL.
• Longest rule wins — the most specific (longest) matching rule decides. If an Allow and a Disallow are equally long, Allow wins (Google and RFC 9309).

IndexNow SubmitterNeeds internet

Submit your sitemap URLs to Bing, Yandex, Seznam, Naver and Yep with IndexNow: load your sitemap, create the key file, verify it and submit in one go.

Meta Tag CheckerNeeds internet

Check any page’s title tag, meta description, canonical, robots and viewport tags online. Free pixel-width meters plus desktop and mobile Google previews.

• Accidental noindex — left over from a staging site — check both the meta robots tag and the X-Robots-Tag HTTP header, which this tool shows side by side.
• Canonical pointing to another URL — , e.g. every page pointing to the home page. Google then may ignore the page entirely.
• Duplicate titles and descriptions — generated from a template. Use the Website Crawler to find them site-wide.

Heading CheckerNeeds internet

Free online heading checker: see every H1–H6 tag of a page as an indented outline, spot skipped levels, missing or multiple H1s and empty headings.

Image Alt CheckerNeeds internet

Free image alt checker: list every image on a page with its alt text, file size, dimensions and format. Find missing alt tags, large and broken images.

• File size — we send a HEAD request for up to 40 images and read their Content-Length. Images over 200 KB are flagged; they slow down Largest Contentful Paint,…
• Width and height attributes — without them the browser can't reserve space before the image loads, so content jumps — measured as Cumulative Layout Shift (CLS), a Core Web Vital.
• Modern formats — WebP and AVIF are typically much smaller than JPEG or PNG at similar quality; SVG is ideal for logos and icons.

Keyword Density CheckerNeeds internet

Free keyword density checker: analyze any URL for keyword placement in title, H1 and URL, top 1-, 2- and 3-word phrases, word count and readability.

• Title tag — the strongest on-page relevance signal and the headline in search results.
• H1 and subheadings — confirm the topic and structure of the page.
• URL — a short, descriptive slug (see the Slug Generator).

Open Graph CheckerNeeds internet

Check Open Graph and Twitter Card tags of any URL. Preview how links look on Facebook, LinkedIn, X and Slack, find missing tags and get a copy-paste fix.

• 1200 × 630 px — (1.91 : 1) works well for Facebook, LinkedIn and Slack. Keep important text away from the edges, as some apps crop to a square or 2 : 1.
• X large card — 2 : 1 aspect ratio, at least 300 × 157 px, under 5 MB. A 1200 × 630 image displays with slight cropping.

Security Headers CheckerNeeds internet

Scan any website’s HTTP security headers online for free: HSTS, CSP, X-Frame-Options and more. Get an A+ to F grade and copy-paste configs for your server.

Website CrawlerNeeds internet

Crawl up to 100 pages of your site free and find broken pages, redirects, duplicate or missing titles and descriptions, H1 problems and noindex tags.

Schema Markup ValidatorNeeds internet

Validate schema.org structured data free: test JSON-LD and microdata from any URL or pasted code and find missing required properties for rich results.

• Syntax — every <script type="application/ld+json"> block is parsed separately, so one broken block (a trailing comma, an unescaped quote) is pinpointed…
• Formats — JSON-LD (including @graph), Microdata (itemscope/itemprop) and RDFa detection.
• Required and recommended properties — for around 30 common types — Article, Product, Offer, Organization, LocalBusiness, BreadcrumbList, FAQPage, Event, Recipe, VideoObject, JobPosting,…

Redirect CheckerNeeds internet

Check any URL’s redirect chain free: see every 301, 302, 307 and 308 hop, status codes and timings, and whether http, https and www versions agree.

HTTP Header CheckerNeeds internet

See the HTTP response headers of any URL free: status code, redirects, caching, content type, X-Robots-Tag and security headers, explained in plain English.

Robots.txt TesterNeeds internet

Test any robots.txt free: see if Googlebot, Bingbot or AI crawlers may crawl a URL, find the matching rule, spot syntax errors and test your edits live.

• Pick the group — A crawler obeys only the group whose User-agent matches it most specifically. If Googlebot has its own group, the User-agent: * rules are ignored for…
• Find matching rules — Each Allow and Disallow path is matched from the start of the URL path, including the query string. * matches any characters and $ anchors the end.
• Longest match wins — The rule with the longest path decides. If an Allow and a Disallow are equally long, Allow wins. No matching rule means allowed.

Sitemap ValidatorNeeds internet

Validate your XML sitemap free: find it via robots.txt, count URLs, check lastmod dates, duplicates and wrong-host URLs, and test the status of listed pages.

• Discovery — whether the sitemap is declared in robots.txt with a Sitemap: line, or only found at a default location.
• Structure — regular URL set or sitemap index, number of URLs and child sitemaps.
• Limits — no more than 50,000 URLs and 50 MB (uncompressed) per sitemap file.

AI Crawler CheckerNeeds internet

Check whether your site allows or blocks AI crawlers like GPTBot, ClaudeBot, PerplexityBot and Google-Extended, see your llms.txt and get a robots.txt fix.

SERP Preview

Preview how your title and meta description look in Google on desktop and mobile. Free SERP snippet tool with pixel-width meters and truncation.

• Front-load the keyword — Put the topic people search for in the first few words, so it survives truncation and gets noticed when users scan.
• Keep the brand short and at the end — Google often shows your site name separately above the URL, so “| Brand Name Inc.” at the end of every title mostly costs space.
• Write descriptions as a promise — Say what the visitor gets — a price, a checklist, a free tool — rather than repeating the title. Google bolds words that match the query, so natural…

Hreflang Generator

Generate hreflang tags for multilingual sites as HTML link tags, HTTP headers or XML sitemap entries. Validates ISO language and region codes. Free.

• Codes — the language is an ISO 639-1 two-letter code (en, de, pt); the optional region is an ISO 3166-1 alpha-2 country code (GB, AT, BR). Region alone is…
• Self-reference — each page must list itself as well as all its alternates.
• Return links — annotations must be reciprocal. If page A points to B, B must point back to A, otherwise Google may ignore the pair. The easiest way is to put the…

llms.txt Generator

Create an llms.txt file in the llmstxt.org format with a summary, sections and link lists. Live preview, validation and download. Free and private.

UTM Builder

Build UTM-tagged campaign URLs for Google Analytics 4 with presets for Google Ads, Meta, LinkedIn and email, consistent lowercase naming and bulk mode. Free.

• Lowercase everything — UTM values are case-sensitive: Email and email appear as separate rows.
• Pick one separator — Use underscores or hyphens consistently instead of spaces, which become %20 or +.
• Never tag internal links — UTMs on links within your own site start a new session and overwrite the original source.

Redirect Generator

Turn old → new URL lists into 301 redirects for .htaccess, Nginx, Netlify, Vercel, Next.js, Cloudflare and Webflow CSV. Detects chains, loops and duplicates.

• Webflow — add redirects in Site settings › Publishing › 301 redirects, or import a CSV there. Source paths must start with / and contain no domain; targets can…
• Apache — Redirect 301 /old /new (mod_alias) matches by prefix, so /old also redirects /old/anything. The RewriteRule format matches exact paths and is safer…
• Nginx — location = /old { return 301 /new; } matches one exact path. For thousands of URLs, a map block is faster to maintain.

security.txt Generator

Create a valid security.txt file (RFC 9116) so security researchers know how to report vulnerabilities. Contact, Expires, Policy, Encryption and more. Free.

humans.txt Generator

Generate a humans.txt file that credits the people who built your website — team, thanks, standards and tools used. Simple form, instant download, free.

• Credit without a footer link — clients often don’t want “Made by …” in their footer, but a humans.txt is invisible to normal visitors.
• Documentation — a quick record of the stack, standards and tools used, useful for whoever maintains the site next.
• Culture — a small, friendly signal that real people built the site.

ads.txt Generator

Create a valid ads.txt file for Google AdSense, Ad Manager and other ad networks. Add DIRECT and RESELLER records with presets, validation and download. Free.

• Ad system domain — the network’s canonical domain (google.com for AdSense and Ad Manager).
• Publisher account ID — your ID in that system.
• Relationship — DIRECT (you control the account) or RESELLER (an intermediary sells your inventory).

.gitignore Generator

Create a .gitignore for your stack: pick languages, frameworks, tools, operating systems and IDEs, merge the rules without duplicates and download the file.

.htaccess Generator

Generate an Apache .htaccess file: force HTTPS, www or non-www, redirects, security headers, gzip and Brotli, browser caching, hotlink protection and more.

Docker Compose Generator

Build a compose.yaml for Node, Python, Postgres, MySQL, MongoDB, Redis, Nginx, WordPress and more — with healthchecks, volumes and a matching .env file.

GitHub Actions Workflow Generator

Generate a GitHub Actions workflow for Node, Python, Go, static sites or Docker: triggers, caching, lint, test, build, matrix and deploy to Pages or Vercel.

Git Command Generator

Describe what you want to do in Git — undo a commit, rename a branch, squash, stash, revert, untrack a file — and get the exact commands with explanations.

Nginx Config Generator

Generate Nginx server blocks for static sites, SPAs, reverse proxies and PHP-FPM, with HTTPS and www redirects, gzip, caching, security headers and rate limits.

• Missing semicolon — every directive ends with ;. nginx -t shows the exact line.
• add_header inheritance — an add_header inside a location replaces all headers from the server level. The generator repeats security headers where needed.
• Trailing slash in proxy_pass — proxy_pass http://app/; strips the location prefix, proxy_pass http://app; keeps it.

.env File Validator

Check a .env file for invalid keys, duplicates, empty values, quoting mistakes and exposed secrets, compare it with .env.example and create a safe example file.

• Duplicate keys — most loaders keep the first or the last value silently, so changes seem to have no effect.
• Spaces around = — or in unquoted values — KEY = value breaks in shells and Docker.
• Unclosed quotes — that swallow the following lines.

Chmod Calculator

Convert Linux file permissions between numeric (755, 644, 4755) and symbolic (rwxr-xr-x) form, with setuid, setgid, sticky bit and ready-to-run chmod commands.

• setuid (4xxx) — an executable runs with the file owner’s rights (e.g. passwd).
• setgid (2xxx) — on folders, new files inherit the folder’s group; handy for shared team folders.
• sticky (1xxx) — on folders, only a file’s owner can delete it.

package.json Generator

Build a valid package.json with npm name checks, scripts for Vite, Next.js, Node or TypeScript libraries, exports, engines, license and repository fields.

Docker Run to Compose

Convert docker run commands to Docker Compose services — ports, volumes, env vars, networks, restart, healthchecks and limits, with warnings for skipped flags.

• Relative paths — in Compose, ./data is relative to the compose file, not your current shell directory.
• Secrets — move passwords from environment to a .env file and reference them as ${DB_PASSWORD}; validate it with the .env File Validator.
• Startup order — add depends_on between services yourself; the Docker Compose Generator shows the healthcheck pattern.

YAML Validator

Validate YAML online and find syntax errors by line: bad indentation, tabs, duplicate keys, multi-document files and YAML 1.1 yes/no gotchas.

Semantic Version Calculator

Compare semantic versions, bump major, minor, patch or prerelease, and test npm ranges like ^1.2.0, ~2.3 or 1.x against your versions — with plain explanations.

Changelog Generator

Paste git log output and get a grouped Markdown changelog: features, fixes, performance and breaking changes, in Keep a Changelog style, with the next version.

.editorconfig Generator

Create an .editorconfig with indentation, line endings, charset, whitespace and final newline rules — presets for web, Node, Python, Go and Makefiles.

.htaccess Tester & Validator

Validate .htaccess syntax and test RewriteRule, RewriteCond and Redirect rules against any URL. See which rules match, the redirect target and every step. Free.

• Unknown directives — and typos — Apache answers any unknown directive in .htaccess with a 500 Internal Server Error.
• Server-only directives — such as ServerName, <VirtualHost> or <Directory>, which are not allowed in .htaccess.
• Unbalanced containers — an <IfModule> or <FilesMatch> that is never closed.

.env.example Generator

Turn a .env file into a safe .env.example: secrets are blanked, safe defaults kept, comments preserved. Or scan your code for process.env and os.environ keys.

• Key names — containing SECRET, TOKEN, PASSWORD, PASS, PWD, KEY, PRIVATE, CREDENTIAL, AUTH, SALT, DSN or WEBHOOK.
• Value patterns — such as Stripe (sk_live_…), GitHub (ghp_…), AWS (AKIA…), Slack, OpenAI and Anthropic keys, JWTs, PEM private keys and URLs with embedded passwords…
• High-entropy strings — long random-looking values are treated as secrets even if the key name looks harmless.

Dockerfile Generator

Generate a production-ready Dockerfile and .dockerignore for Node.js, Next.js, Python, Go, Java, PHP, Ruby, .NET, Rust or static sites, with multi-stage builds.

• Multi-stage builds — compile in a full image, then copy only the output into a slim runtime image. Compilers, dev dependencies and source code stay out of production.
• Layer caching — copy the dependency manifest (package.json, requirements.txt, go.mod…) and install before copying the rest of the code, so a code change doesn’t…
• A non-root user — if the app is compromised, the attacker doesn’t get root inside the container.

Kubernetes YAML Validator

Validate Kubernetes manifests online: YAML syntax, required fields, deprecated apiVersions, selector mismatches, resource limits, probes and security.

GitHub Actions Workflow Validator

Check GitHub Actions workflows before you push: triggers, jobs, steps, needs, expressions, cron, permissions, outdated actions and injection risks.

• Unknown events or keys — typos such as pull-request instead of pull_request, or run-on instead of runs-on.
• Broken job graphs — needs pointing at a job that doesn’t exist, or jobs that depend on each other in a cycle.
• Expressions — unbalanced &#36;{{ }}, unknown contexts and references to step outputs that don’t exist.

Git Cheat Sheet

Interactive Git cheat sheet: branch, commit, merge, rebase, stash, undo and history commands explained in one line. Fill in your branch name and copy.

Docker Cheat Sheet

Interactive Docker cheat sheet: build, run, exec, logs, Compose, volumes, networks and cleanup commands. Fill in your image and container names and copy.

Linux Commands Cheat Sheet

Interactive Linux and bash cheat sheet: files, grep, find, permissions, processes, systemd, networking, SSH and rsync. Fill in your paths and copy commands.

AI Prompts for Developers

28 copy-paste AI prompts for developers: debugging, code review, refactoring, tests, SQL, commit messages and docs. Works with ChatGPT, Claude and Copilot.

• Context — language, framework and versions. “React 19 with TypeScript” gets far better answers than “JavaScript”.
• Expected vs actual — for bugs, say what should happen and what happens instead.
• The smallest relevant code — paste the function and its callers, not the whole repository.

JSON Formatter

Free online JSON formatter and validator. Beautify or minify JSON, find errors by exact line and column, sort keys and explore a collapsible tree view.

Mock Data Generator

Generate realistic fake test data: users, products, orders, addresses and nested API records in 5 locales. Export JSON, CSV, SQL INSERT or TypeScript — free.

• JSON — seed a mock API, a JSON server or a Webflow CMS import after converting with the JSON to CSV converter.
• CSV — import into spreadsheets, Airtable or the Webflow CMS (nested values are flattened to JSON strings).
• SQL INSERT — fill a local PostgreSQL, MySQL, SQLite or SQL Server table; values are escaped and quoted for the dialect.

JSON to Types

Paste JSON and get typed models for TypeScript, Python, Go, Java, C#, Kotlin, Swift and Rust — with optional fields, nullables, dates and nested types. Free.

• Arrays of objects are merged — a field that’s missing in some items becomes optional; a field that is sometimes null becomes nullable.
• Numbers — whole numbers become integer types (int, int64, long, i64); anything with decimals becomes a float/double.
• Dates — ISO 8601 strings like 2026-10-26T09:30:00Z can become Date, datetime, time.Time, OffsetDateTime, DateTimeOffset or DateTime<Utc>.

JSON Viewer

View JSON as a collapsible tree: expand and collapse nodes, search keys and values, see types and sizes and copy the JSON path of any value. Free.

• Collapsible nodes — with item and key counts on every object and array.
• Type colors — strings, numbers, booleans and null are easy to tell apart.
• Search — highlights matching keys and values and opens the branches that contain them.

JSON Schema Validator

Validate JSON against a JSON Schema (draft 2020-12, 2019-09, 07 or 04) with clear error paths, format checks and a schema generator for sample data.

JSONPath Tester

Test JSONPath expressions against your JSON online: filters, wildcards, recursive descent and slices, with every match listed by path and value.

OpenAPI / Swagger Validator

Validate OpenAPI 3.1, 3.0 and Swagger 2.0 specs in YAML or JSON against the official schemas, plus broken $refs, duplicate operationIds and path parameters.

• Swagger 2.0 — swagger: "2.0", definitions, host/basePath.
• OpenAPI 3.0 — components, servers, requestBody; schemas are a JSON Schema draft-04 subset with nullable.
• OpenAPI 3.1 — fully aligned with JSON Schema 2020-12 (type: [string, "null"] instead of nullable), adds webhooks.

JSON to YAML

Convert JSON to clean, readable YAML instantly — and edit the YAML to get JSON back. Free online converter with indent and quoting options. No upload.

YAML to JSON

Convert YAML to JSON online for free. Supports anchors, merge keys and multi-document files, and shows YAML errors with line and column. Runs in your browser.

• Anchors, aliases and merge keys — &defaults, *defaults and <<: *defaults (common in Docker Compose and GitLab CI) are expanded into plain JSON.
• Multiple documents — files with several documents separated by --- (typical for Kubernetes) become a JSON array, one element per document.
• Block scalars — | keeps line breaks, > folds them into spaces.

JSON to CSV

Convert JSON arrays to CSV online for free. Flattens nested objects with dot notation, handles arrays and quoting, and exports Excel-ready CSV or TSV files.

CSV to JSON

Convert CSV to JSON online for free. Auto-detects the delimiter, handles quoted fields with commas and line breaks, detects numbers and rebuilds nested objects.

JSON to TypeScript

Generate TypeScript interfaces or type aliases from JSON instantly. Free online converter with nested types, optional and nullable fields and array merging.

JSON to XML

Convert JSON to XML online. Maps arrays to repeated elements and @-prefixed keys to attributes, with a custom root element, indentation and declaration.

XML to JSON

Convert XML to JSON online. Attributes become @-prefixed keys, repeated elements become arrays, CDATA and text are kept; optional type detection.

JSON Diff

Compare two JSON documents and list every added, removed and changed value with its path. Ignores key order and, optionally, array order and case.

JSON Escape & Unescape

Escape text for use inside JSON strings, unescape \n, \" and \u sequences, embed a JSON document as a string and parse it back. ASCII-only option.

JSON to Markdown Table

Convert a JSON array (API responses, LLM output) into a neatly aligned Markdown table. Flattens nested objects, right-aligns numbers and escapes pipes. Free.

• Columns — are the union of keys across all objects, in first-seen order; missing values become empty cells.
• Nested objects — are flattened (address.city); arrays and deeper structures are shown as compact JSON.
• Alignment — in Auto mode, numeric columns are right-aligned with ---: so figures line up.

GraphQL Formatter & Validator

Format, minify and validate GraphQL queries and schemas. See syntax errors with line and column and check queries against your schema SDL. Runs locally.

GraphQL Query Builder

Build GraphQL queries and mutations visually: paste your schema, tick the fields you need, fill in arguments and copy the query with its variables JSON.

CSV & Excel to SQL

Convert CSV or Excel to SQL INSERT statements online. Detects column types, writes CREATE TABLE and supports MySQL, PostgreSQL, SQLite, SQL Server and Oracle.

• Quotes — inside text are doubled (O'Brien → 'O''Brien'); MySQL output also escapes backslashes.
• Identifiers — are quoted with backticks (MySQL), double quotes (PostgreSQL, SQLite, Oracle) or brackets (SQL Server), so reserved words like order or group work as…
• Multi-row inserts — are much faster than one statement per row. SQL Server allows at most 1,000 rows per VALUES list, and Oracle uses INSERT ALL … SELECT 1 FROM DUAL.

SQL Playground

Run SQL online with a real SQLite database in your browser. Sample tables included, import CSV, run multiple statements, export results and save the database.

SQL Validator

Validate SQL syntax for MySQL, PostgreSQL, SQL Server, SQLite, BigQuery and Snowflake. See the exact line and column of errors plus best-practice warnings.

• Identifier quotes — MySQL and MariaDB use backticks (`order`), PostgreSQL, SQLite and the SQL standard use double quotes, SQL Server uses square brackets ([order]).
• Row limits — LIMIT 10 in MySQL, PostgreSQL and SQLite; TOP 10 or OFFSET … FETCH in SQL Server.
• Upserts — ON DUPLICATE KEY UPDATE (MySQL) vs ON CONFLICT … DO UPDATE (PostgreSQL, SQLite) vs MERGE (SQL Server, Snowflake, BigQuery).

Excel to JSON

Convert Excel spreadsheets to JSON online for free. Open .xlsx files or paste cells, pick a sheet, keep dates and numbers, and export an array of objects.

• Old .xls files — use a binary format. Save them as .xlsx or CSV in Excel (File → Save As) first.
• Merged cells — only keep their value in the top-left cell; the others come through empty.
• Duplicate column names — are renamed name_2, name_3 so no data is overwritten.

JSON to Excel

Convert JSON to an Excel .xlsx file online for free. Flattens nested objects into columns, keeps numbers as numbers, bolds and freezes the header row.

• Types survive — Numbers are stored as numbers and booleans as TRUE/FALSE, so formulas such as =SUM() work immediately.
• No encoding issues — Accents, emoji and non-Latin scripts display correctly; CSV files often need a UTF-8 BOM for Excel.
• No delimiter guessing — Excel in many European locales expects semicolons in CSV files; an .xlsx file has no delimiter at all.

JSON to SQL

Convert JSON arrays to SQL INSERT and CREATE TABLE statements for MySQL, PostgreSQL, SQLite, SQL Server or Oracle. Flattens nested objects. Free and private.

• Numbers — integers become INT (or BIGINT above 2,147,483,647); decimals become DECIMAL with enough precision for the largest value.
• Booleans — TRUE/FALSE in MySQL and PostgreSQL, 1/0 in SQLite, SQL Server (BIT) and Oracle.
• Strings that look like dates — (2026-02-14 or ISO timestamps) become DATE or DATETIME/TIMESTAMP columns.

SQL to JSON, CSV & Excel

Convert SQL INSERT statements and mysqldump files to JSON, CSV or Excel online. Reads CREATE TABLE column names, handles escapes and multiple tables.

• Multi-row inserts — VALUES (…), (…), (…) as written by mysqldump and most export tools.
• Column names — from the INSERT column list, or — when the INSERT has none — from the matching CREATE TABLE in the same script.
• Quoted identifiers — `backticks`, "double quotes" and [brackets], plus schema-qualified names like public.users.

CSV & Excel to HTML Table

Convert CSV, Excel or JSON to a clean HTML table online. Semantic thead markup, escaped cells, optional Bootstrap classes or built-in CSS and a live preview.

CSV & Excel to Markdown Table

Convert CSV, Excel cells or JSON to a Markdown table online. Padded columns, escaped pipes and right-aligned numbers — ready for GitHub, READMEs and docs.

• Pipes — (|) inside a cell would start a new column, so they are escaped as \|.
• Line breaks — end a table row in Markdown. They are converted to <br> (which GitHub renders) or to spaces.
• Backslashes — are escaped so they appear literally.

Excel, CSV & JSON to PHP Array

Convert CSV, Excel or JSON to a PHP array online. Associative or indexed arrays, short [] or array() syntax, keyed by ID, properly escaped strings. Free.

Excel, CSV & JSON to JS Array

Convert CSV, Excel or JSON to a JavaScript array of objects online. const, export or module.exports, unquoted keys, single or double quotes, trailing commas.

• Unquoted keys — when the key is a valid identifier (name:), quoted only when needed ('first name':).
• Single or double quotes — to match your Prettier or ESLint settings.
• Trailing commas — , which keep diffs to one line when you add rows.

CREATE TABLE Generator

Build SQL CREATE TABLE statements for MySQL, PostgreSQL, SQLite, SQL Server and Oracle. Primary keys, auto-increment, defaults, or infer columns from data.

• PRIMARY KEY — uniquely identifies each row and implies NOT NULL. Tick PK on several columns for a composite key.
• NOT NULL — rejects missing values. Use it for every column your application always fills.
• UNIQUE — prevents duplicates, such as two accounts with the same email.

SQL IN Clause Generator

Turn a list of values or an Excel column into a SQL IN clause. Quotes and escapes values, removes duplicates and splits into groups of 1,000 for Oracle. Free.

• Oracle — allows at most 1,000 expressions in one IN list (error ORA-01795). Set groups of 1,000 and the generator joins them with OR.
• SQL Server — has no fixed limit, but statements with many thousands of values parse slowly; use a temporary table or table-valued parameter instead.
• MySQL — is limited by max_allowed_packet; PostgreSQL can also take an array: WHERE id = ANY('{1,2,3}').

MySQL Syntax Checker

Check MySQL and MariaDB query syntax online. Pinpoints the line and column of every error and warns about UPDATE without WHERE, SELECT * and more.

• Casts — PostgreSQL accepts value::int; most others need CAST(value AS INT).

PostgreSQL Syntax Checker

Check PostgreSQL query syntax online: CTEs, ::casts, RETURNING, ON CONFLICT and JSON operators. Shows the line and column of each error. Free and private.

Excel Formula to JavaScript

Convert Excel and Google Sheets formulas to JavaScript. Translates IF, SUMIFS, VLOOKUP, XLOOKUP, ROUND, text and date functions with Excel-accurate helpers.

• Operator precedence — In Excel =-2^2 is 4 because negation binds tighter than ^. JavaScript does not even allow -2 ** 2. The converter always adds the parentheses Excel…
• Rounding — Excel rounds halves away from zero; Math.round(-2.5) returns −2 and (1.005).toFixed(2) gives "1.00". The generated round() helper matches Excel.
• Remainders — MOD(-7, 3) is 2 in Excel but -7 % 3 is −1 in JavaScript, so a mod() helper is used.

Excel Formula to Python

Convert Excel formulas to Python code online. Translates IF, SUMIFS, COUNTIF, VLOOKUP, ROUND and text functions into clean Python with Excel-accurate rounding.

• Banker's rounding — Python's round(2.5) returns 2 and round(0.125, 2) returns 0.12; Excel gives 3 and 0.13. The output uses an excel_round() helper based on Decimal with…
• Concatenation — "Total: " + 5 raises a TypeError in Python, so every non-text operand of & is wrapped in str().
• IF is an expression — IF becomes Python's conditional expression (a if c else b), and nested IFs chain naturally.

Excel Formula to PHP

Convert Excel formulas to PHP code online. Translates IF, VLOOKUP, SUMIFS, IFERROR, text and date functions into PHP 8 with multibyte-safe string handling.

• Nested ternaries — Since PHP 8, unparenthesized nested ternaries are a fatal error. Every nested IF is wrapped in parentheses automatically.
• Concatenation precedence — In PHP 8, + and - bind tighter than ., so "Total: " . $a + $b adds first. The converter keeps Excel's meaning either way.
• Multibyte text — LEFT, MID, LEN, UPPER and LOWER use the mb_* functions, so accented characters and emoji count as one character, like in Excel.

Excel Formula to SQL

Convert Excel formulas to SQL for MySQL, PostgreSQL or SQL Server. IF becomes CASE WHEN, SUMIFS and COUNTIF become conditional aggregates. Free and private.

JavaScript Minifier

Minify JavaScript online with Terser. Mangle names, drop dead code and console calls, keep license comments, support ES modules and see the gzipped size. Free.

• Syntax error — the line and column are shown. TypeScript and JSX must be compiled to JavaScript first.
• Code stops working after mangling — turn off Mangle top-level names; if that does not help, check for eval or code that reads function names.
• Need a readable version again? — Use the JavaScript formatter to beautify minified code.

Website Compression TestNeeds internet

Check if a website uses gzip, Brotli or Zstandard compression. See transfer sizes, savings, uncompressed CSS/JS files and how small the page could be.

• Each encoding separately — the page is requested with identity, br, gzip, zstd and a browser-like combined header, and the real transferred bytes are measured.
• Potential savings — the uncompressed page is compressed on our server with gzip 6, gzip 9, Brotli 5 and Brotli 11, so you can see what you are leaving on the table.
• Linked CSS and JavaScript — up to 12 stylesheets and scripts from the page are checked, because it is common for HTML to be compressed while static files are not.

SVG Optimizer

Optimize SVG files online with SVGO: remove editor metadata, simplify paths, round numbers and minify markup. Live before/after preview and size savings. Free.

Gzip Compress & Decompress

Gzip compress or decompress text and files online. Choose levels 1–9, zlib or raw deflate, view Base64 output, open .gz files and compare with Brotli. Private.

• “Invalid data” — usually means the input is Brotli, or the Base64 was cut off. Try the Brotli tab, or check the string is complete.
• A .tar.gz file — decompresses to a .tar archive, which you can then open with any archive tool.
• Already-compressed files — (JPEG, MP4, ZIP) do not get smaller — the data has no redundancy left.

Brotli Compress & Decompress

Compress or decompress Brotli (.br) online with quality 0–11. Compare Brotli with gzip for your text or files. Runs in your browser, nothing uploaded.

• Size — Brotli wins on almost all text; the gap is largest for small files thanks to the built-in dictionary.
• Speed — at quality 11 Brotli is much slower to compress than gzip -9; at quality 4–5 it is comparable.
• Support — all current browsers accept Brotli over HTTPS. gzip remains the safe fallback for old clients and tools.

HTML Minifier

Minify HTML online: remove comments and whitespace, collapse boolean attributes and minify inline CSS and JavaScript. Keeps pre and textarea intact.

JSON Minifier

Minify JSON online: remove whitespace and line breaks, validate the syntax, sort keys and convert arrays to JSON Lines. Shows minified and gzipped size.

• API responses and config shipped to browsers — fewer bytes over the network.
• Storing JSON — in databases, Redis, cookies, environment variables or query strings where size limits apply.
• Embedding JSON-LD — or app state in HTML.

XML Minifier

Minify XML online: remove comments, indentation and whitespace between tags while keeping CDATA and text intact. Validates well-formedness and shows savings.

ZIP File Creator

Create ZIP files online from files and folders. Pick the compression level, keep folder structure and download instantly. Files never leave your device.

• Nothing is uploaded — confidential documents never leave your computer.
• It is fast — no upload or download wait for large files.
• There is no file-size limit — imposed by a server; the practical limit is your device’s memory (a few gigabytes on a desktop).

Unzip Files Online

Unzip files online: open a ZIP archive, see every file and folder, preview text and images and download single files. Runs in your browser, nothing uploaded.

• Password-protected ZIPs — encryption is not supported; you will see a clear message.
• RAR, 7z and tar.gz — these are different formats. A .gz file can be decompressed with the gzip tool.
• Very large archives — the whole archive is held in memory, so multi-gigabyte files may not open on phones.

Merge PDF

Merge PDF files online for free. Drag to set the order, combine any number of PDFs into one document and download instantly. Files stay on your device.

JPG to PDF

Convert JPG, PNG and WebP images to PDF online. Combine many photos into one PDF, choose A4, Letter or fit-to-image pages and margins. Nothing is uploaded.

PDF to JPG

Convert PDF pages to JPG or PNG images online. Choose 72, 150 or 300 DPI, download single pages or all as ZIP. Rendered in your browser, nothing uploaded.

Split PDF

Split a PDF online: extract page ranges into a new PDF, or split every page or every N pages into separate files downloaded as a ZIP. Free and private.

Compress PDF

Reduce PDF file size by recompressing and downscaling images and packing the file structure. Choose a compression level. Private: runs in your browser.

• Downscales images — to a sensible resolution for the chosen level and re-encodes them as JPEG.
• Keeps the original — of any image the new version wouldn’t make smaller.
• Packs the file structure — into compressed object streams and deflates any uncompressed page content.

Protect PDF (Add Password)

Password-protect a PDF with AES-256 encryption and choose whether printing, copying or editing is allowed. Runs in your browser — the file is never uploaded.

Rotate PDF

Rotate PDF pages online and save them permanently. Turn single pages or the whole document 90° or 180°, preview with thumbnails, download instantly. Free.

Organize PDF (Reorder & Delete Pages)

Reorder, delete and rearrange PDF pages online. Drag thumbnails into a new order, remove pages you do not need and download the result. Free, nothing uploaded.

• Reverse order — fixes documents scanned back-to-front.

Add Watermark to PDF

Add a text watermark to every page of a PDF: CONFIDENTIAL, DRAFT or your name. Set size, color, opacity, angle and tiling with a live preview. Free and private.

Add Page Numbers to PDF

Add page numbers to a PDF online. Choose position, format (1, Page 1 of N, 1 / N), starting number, size and margins, and skip the cover page. Free and private.

• Skip first page — leaves the cover unnumbered and starts counting on page 2 (with the number you choose, usually 1).
• Start at — continues numbering from a previous document, for example 45 for the second volume.
• Mirror — puts numbers on the outer edge — right on odd pages, left on even pages — like a printed book.

Bcrypt Generator & Checker

Generate bcrypt password hashes with a chosen cost factor and verify a password against an existing bcrypt hash. Supports $2a$, $2b$ and $2y$.

JWT Decoder

Decode JWTs online for free: see the header, payload and claims with readable exp/iat dates and expiry status, and verify HS256, RS256 or ES256 signatures.

• Header — JSON describing the token, e.g. {"alg":"HS256","typ":"JWT"}.
• Payload — JSON with the claims: who the user is, what they may do and when the token expires.
• Signature — computed over header.payload with a secret or private key, so any change to the first two parts invalidates it.

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of text or files online. Free, with HMAC, hex or Base64 output and a checksum compare field.

Htpasswd Generator

Create .htpasswd entries for Apache and Nginx Basic Auth with bcrypt, APR1-MD5 or SHA1. Add several users, copy the lines or download the file. Runs locally.

HMAC Generator

Generate HMAC-SHA256, SHA-384, SHA-512 and SHA-1 signatures online. Hex or Base64 output, text, hex or Base64 keys, and webhook signature verification.

JWT Encoder

Create signed JSON Web Tokens online with HS256, HS512, RS256, PS256 or ES256. Edit header and payload, add iat/exp claims and sign with a secret or key.

RSA Key Generator

Generate RSA 2048–4096, ECDSA P-256/P-384 and Ed25519 key pairs in your browser. Download PKCS#8 and SPKI PEM, OpenSSH and JWK public keys. Never uploaded.

• PKCS#8 PEM — (BEGIN PRIVATE KEY) — the standard private key format for OpenSSL, Node.js, Java, Go and the JWT encoder.
• SPKI PEM — (BEGIN PUBLIC KEY) — the public key to share with whoever verifies your signatures.
• OpenSSH — (ssh-rsa AAAA…) — for authorized_keys. For SSH key pairs with an OpenSSH private key, use the SSH key generator.

SSH Key Generator

Generate SSH key pairs online: Ed25519, RSA 4096 or ECDSA. Get an OpenSSH private key and an authorized_keys public key with fingerprint. Runs locally.

SSL Certificate Decoder

Decode SSL/TLS certificates in PEM or DER: subject, issuer, validity, SANs, key size, extensions and SHA-256 fingerprint, for a whole chain. Runs locally.

• Name mismatch — the hostname is not in the SAN list.
• Expired / not yet valid — check the dates and the server’s clock.
• Incomplete chain — paste the whole chain the server sends; the intermediate’s subject must match the leaf’s issuer.

CSR Decoder

Decode a Certificate Signing Request (CSR) to check its subject, domains (SANs), key type, size and signature before sending it to a certificate authority.

• Domains — every hostname — including www and bare domain — must appear in the SAN list. Many CAs copy the CN into the SANs, but not all.
• Key — RSA 2048 bits or more, or ECDSA P-256 / P-384. Smaller RSA keys are rejected.
• Organization fields — for OV/EV certificates, O, L, ST and C must match your legal registration exactly. For DV certificates they are ignored.

AES Encrypt & Decrypt

Encrypt and decrypt text with AES-256 and a password: modern AES-GCM with PBKDF2, or OpenSSL-compatible aes-256-cbc output. Runs in your browser.

Online HTML Editor

Write HTML, CSS and JavaScript with a live preview and console in your browser. Sandboxed, autosaved and downloadable as one HTML file. No sign-up.

• Tab — inserts two spaces instead of leaving the editor.

Regex Tester

Test regular expressions online with live match highlighting, capture and named groups, replace mode, presets and a cheat sheet. Free JavaScript regex tester.

Diff Checker

Compare two texts or code files online and see every difference highlighted down to the word. Side-by-side or inline view, ignore whitespace or case. Free.

• Ignore whitespace — treats runs of spaces and tabs as a single space and ignores leading and trailing whitespace — perfect when one file was re-indented.
• Ignore case — treats “Error” and “error” as equal.
• Collapse unchanged — hides long unchanged stretches, keeping three lines of context around each change. Click a collapsed row to expand it.

README Generator

Create a professional README.md with badges, install steps, usage, config table, env vars, roadmap and license. Live GitHub-style preview, free and private.

• Lead with the outcome — , not the technology: “Turn any string into a URL-safe slug” beats “A TypeScript utility using Unicode normalization”.
• Make examples copy-pasteable — and runnable — no placeholders that break when pasted.
• Use relative links — for files in the repo (./docs/setup.md, LICENSE) so they work on forks and branches.

HTML Formatter

Free online HTML formatter: beautify messy or minified HTML with clean indentation, format inline CSS & JS, or minify HTML safely — all in your browser.

CSS Formatter

Beautify minified or messy CSS online for free: one declaration per line, consistent indentation, clean media queries — or minify it again in one click.

• Two-space indentation — is the de-facto standard in most CSS style guides and the Prettier default.
• One selector per line — in grouped selectors makes diffs smaller when you add or remove a selector.
• A blank line between rules — improves scanning in long files.

JavaScript Formatter

Beautify minified or messy JavaScript online for free. Readable indentation, brace styles, JSX support — plus a safe whitespace minifier. Runs in your browser.

• “Doesn’t parse as plain JavaScript” — shown for TypeScript, JSX or a real syntax error. Formatting still works; minify requires valid JavaScript.
• JSON — formats fine here, but the JSON Formatter also validates it and points to the exact error.

CSS Minifier

Minify CSS online for free: strip comments and whitespace, shorten colours, numbers and zero units safely, and see the size before and after, including gzip.

SQL Formatter

Format SQL queries online for free. Pick MySQL, PostgreSQL, SQL Server, SQLite, BigQuery and more, set keyword case and indentation, and copy clean SQL.

cURL to Code

Convert curl commands to JavaScript fetch, Axios, Node.js, Python requests, PHP cURL and Go code. Handles headers, JSON, forms, auth and file uploads. Free.

• JavaScript fetch — built into every browser. Cross-origin requests also need the server to send CORS headers, and browsers refuse to set headers like Cookie or Host;…
• Node.js fetch — built into Node 18+, no dependency needed; file uploads use fs.openAsBlob.
• Axios — popular for its interceptors and automatic JSON handling.

XML Formatter

Format and validate XML online. Pretty-print with 2 or 4 spaces or tabs, keep text and CDATA intact, and find well-formedness errors by line. Free and private.

JavaScript Keycode Finder

Press any key to see its JavaScript event.key, event.code, keyCode and which values, location and modifiers, plus a ready-to-use keydown handler.

XPath Tester

Test XPath expressions against XML or HTML and see every matching node highlighted, with attributes, text and paths. Namespaces supported. Free and private.

Markdown to HTML

Convert Markdown to clean HTML online with a live preview. Supports GitHub-flavored tables, task lists and fenced code. Free, private, copy or download.

• Line breaks become <br> — standard Markdown joins lines within a paragraph; GitHub comments instead treat every newline as a line break. Enable this to match comment-style…
• Heading IDs — adds GitHub-style id attributes (lowercase, hyphenated, de-duplicated with -1, -2) so you can link to #installation or build a table of contents.
• Full HTML document — wraps the output in <!doctype html>, <head> and <body>, using the first heading as the <title>.

HTML to Markdown

Convert HTML or rich text from web pages and docs into clean Markdown. GFM tables, heading, bullet and code block styles. Free online and fully private.

Cron Expression Generator

Build cron expressions from simple dropdowns or paste one to get a plain-English explanation and the next run times. Free online crontab helper.

• Forgetting the minute — * 9 * * * runs 60 times between 09:00 and 09:59. Use 0 9 * * * to run once.
• Time zones — Cron uses the server's time zone; GitHub Actions and most cloud schedulers use UTC. Switch the run list to UTC to compare.
• Uneven steps — */45 in the minute field fires at :00 and :45, then :00 again — steps restart each hour, they don't carry over.

SPF, DKIM & DMARC CheckerNeeds internet

Check a domain’s email setup: MX records and provider, SPF validity and 10-lookup limit, DKIM selectors, DMARC policy, MTA-STS, TLS-RPT and BIMI — with fixes.

• Two SPF records — adding a new tool often adds a second v=spf1 record. Only one is allowed; merge them.
• More than 10 DNS lookups — every include: counts, including nested ones. Over 10 causes a permanent SPF error. Remove unused services or flatten the record.
• DMARC stuck at p=none — monitoring is a start, but only quarantine or reject actually protects your domain.

Webhook TesterNeeds internet

Get a free webhook URL and inspect incoming requests live: method, headers, query and body. Verify GitHub, Stripe and Shopify signatures. No sign-up.

• Method and path — anything after your URL is captured, so you can use /orders, /refunds etc. to tell events apart.
• Headers — content type, user agent, event names (X-GitHub-Event, Stripe-Signature, X-Shopify-Topic) and delivery IDs.
• Query string and body — JSON is pretty-printed, form posts are decoded into a table, binary bodies are shown as base64.

Subnet Calculator

Calculate network address, broadcast, host range, subnet and wildcard masks from any IPv4 or IPv6 CIDR. Split a network into smaller subnets. Free and instant.

• 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 — private networks (RFC 1918), not routed on the internet.
• 100.64.0.0/10 — carrier-grade NAT shared space.
• 169.254.0.0/16 — link-local, used when DHCP fails.

DNS LookupNeeds internet

Look up DNS records for any domain: A, AAAA, CNAME, MX, TXT, NS, SOA and CAA with TTLs, plus SPF and DMARC checks for email deliverability. Free online.

• CNAME at the root — a bare domain can’t have a CNAME next to its NS/SOA records — use your DNS provider’s ALIAS/ANAME/flattening, or A records.
• Two SPF records — merge them into one, or both become invalid (permerror).
• Old records after a migration — stale A records or a leftover AAAA record can send part of your traffic to the old server. Then check the certificate with the SSL Checker.

SSL CheckerNeeds internet

Check any website’s SSL/TLS certificate: validity, expiry date and days left, issuer, SANs, hostname match, TLS version, cipher and the full chain. Free online.

• Days left — Let’s Encrypt certificates last 90 days and are renewed automatically around day 60. For all public certificates the CA/Browser Forum is shortening…
• Subject Alternative Names (SANs) — the hostnames the certificate covers. example.com and www.example.com are separate names; a wildcard *.example.com covers one level of subdomains but…
• Chain — the leaf certificate, one or more intermediates and the root. Servers must send the intermediates; a missing one causes “unable to verify the first…

MIME Type Lookup

Find the MIME type for any file extension and back — web, images, fonts, video, audio, documents, archives — with Nginx/Apache snippets and file detection.

• JavaScript modules — served as text/plain are blocked: “Failed to load module script… strict MIME type checking”.
• Fonts — served as application/octet-stream may be rejected or not cached; use font/woff2.
• SVG — without image/svg+xml shows as text or a download instead of an image.

Ping TestNeeds internet

Ping any website, domain or IP online: TCP ping latency in milliseconds, min/avg/max, jitter and failed attempts — from our server, no install needed.

• Refused — the host is reachable but nothing listens on that port. Try 80 or 443.
• Timeout — a firewall drops the packets, or the host is down. Check with the Port Checker and the Website Down Checker.
• Doesn’t resolve — check the domain’s records with DNS Lookup.

Port CheckerNeeds internet

Check if ports are open on any domain or public IP: HTTP, HTTPS, SSH, FTP, SMTP, IMAP, MySQL, RDP and more. Shows open, closed or filtered per port.

WHOIS LookupNeeds internet

See who a domain is registered with: registrar, creation and expiry date, domain age, status, nameservers and DNSSEC — or the network owner of an IP address.

DNS Propagation CheckerNeeds internet

Check if your DNS change has propagated: compare A, AAAA, CNAME, MX, TXT and NS answers from Cloudflare, Google, NextDNS, AdGuard and 8 world regions.

• Lower the TTL in advance — set it to 300 seconds a day before a migration, then raise it again afterwards.
• Webflow — point the root domain with A records to Webflow’s IPs and www with a CNAME to proxy-ssl.webflow.com (check Webflow’s current values in the hosting…
• Flush your own cache — if your computer still shows the old site (for example ipconfig /flushdns on Windows).

What Is My IPNeeds internet

See your public IP address (IPv4 or IPv6) instantly, plus your browser, OS, screen size, timezone and the HTTP headers your browser sends. Free, no tracking.

URL Parser

Parse any URL into protocol, host, port, path, query parameters and fragment. Decode and edit query parameters, remove UTM tracking and rebuild the URL.

What Is My Screen Resolution

See your screen resolution, browser viewport size, device pixel ratio and physical pixels instantly — updated live as you resize, plus colour depth.

• Screen resolution — is the size of the whole display in CSS pixels (screen.width × screen.height).
• Viewport — is the area of the browser window available to the page (innerWidth × innerHeight); this is what CSS media queries use.
• Device pixel ratio (DPR) — is the number of physical pixels per CSS pixel. A phone with DPR 3 and a 390-pixel-wide viewport actually has 1170 physical pixels across.

User Agent Parser

Parse any user agent string into browser, version, rendering engine, OS, device type and vendor. Detects Googlebot, Bingbot, GPTBot, ClaudeBot and more. Free.

• Bots first — dozens of crawler tokens are matched — search engines (Googlebot, Bingbot, YandexBot, Applebot), AI crawlers (GPTBot, OAI-SearchBot, ClaudeBot,…
• Browser — specific browsers (Edge, Opera, Samsung Internet, Vivaldi, Yandex, in-app browsers) are checked before the generic Chrome, Firefox and Safari tokens.
• Engine — Blink for Chromium browsers, Gecko for Firefox, WebKit for Safari — and for every browser on iOS, because Apple requires WebKit there (outside the…

Website Down CheckerNeeds internet

Is a website down for everyone or just you? Check any site from our server and get the HTTP status, response time, page title and fixes if it’s only you. Free.

• Reload without cache — Ctrl+Shift+R (Cmd+Shift+R on Mac) or try a private window.
• Flush your DNS cache — ipconfig /flushdns on Windows, sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder on macOS. A recently migrated site may still resolve to…
• Switch networks — disable your VPN or proxy, or try mobile data instead of Wi-Fi — corporate and school networks often block sites.

API TesterNeeds internet

Test REST APIs online: send GET, POST, PUT, PATCH and DELETE requests with params, headers, JSON body and auth, inspect the response and copy it as cURL. Free.

• Method — what you want to do: GET reads, POST creates, PUT replaces, PATCH partially updates, DELETE removes. HEAD returns headers only, OPTIONS asks which…
• URL & query parameters — e.g. /v1/users?page=2&limit=50. Values are URL-encoded automatically when you edit them in the Params table.
• Headers — metadata such as Accept: application/json, Content-Type or an API key header.

HTTP Status Codes

Searchable list of all HTTP status codes from 100 to 511 — 200, 301, 302, 404, 429, 500, 503 and more — with what each means, when to use it and its SEO impact.

Clamp Calculator

Calculate fluid CSS clamp() values for font sizes and spacing from min/max sizes and viewports, preview them live and generate a full fluid type scale. Free.

• Slope — = (24 − 16) ÷ (1440 − 375) = 0.007512 — the size grows 0.0075px per pixel of viewport.
• vw part — = slope × 100 = 0.7512vw, because 1vw is 1% of the viewport width.
• Intercept — = 16 − 0.007512 × 375 = 13.183px = 0.8239rem at a 16px root.

CSS Hover Animation Generator

Make CSS hover effects for buttons, cards and icons: grow, lift, tilt, buzz, glow and more. Tune the keyframes and timing, then copy the CSS.

• Keyframe timeline — add as many keyframes as you like, drag them to new percentages, and give each its own easing.
• Properties — translate X/Y, rotate, 3D rotate X/Y, scale, skew, opacity, blur, glow (box-shadow), background color and border radius. Missing values are…
• Triggers — on load, hover, click, when scrolled into view, or a CSS-only scroll-driven animation.

CSS Keyframes Generator

Build CSS @keyframes on a visual timeline: add, drag and ease each keyframe, scrub frame by frame, import existing keyframes and copy the CSS.

• Stagger — animate a list one item after another with a single CSS custom property.
• Inspect — pause, scrub frame by frame, slow down to ¼ speed and switch on onion skin to see every keyframe at once.
• Export — CSS shorthand or longhand, HTML, JavaScript, Tailwind v3 and v4, a SCSS mixin, a standalone demo file or a share link.

CSS Animation Generator

Create CSS animations visually: keyframe timeline, 50+ presets, easing curves, hover/scroll triggers and stagger. Copy CSS, Tailwind or HTML. Free.

Cubic Bezier Generator

Drag handles to design a CSS cubic-bezier() easing, compare it live against ease and others, or generate spring and bounce curves with linear().

CSS Loader Generator

Create pure CSS loaders and spinners: rings, dots, bars, ripple, pulse, progress and more. Set size, colours, thickness and speed, then copy HTML & CSS.

CSS Gradient Generator

Create linear, radial and conic CSS gradients visually: drag colour stops, set angles, use OKLCH interpolation and copy clean CSS with a fallback. Free online.

Box Shadow Generator

Build layered CSS box-shadow and text-shadow effects visually: offsets, blur, spread, colour, inset, realistic and neumorphism presets. Copy the CSS free.

PX to REM Converter

Convert px to rem and rem to px (plus em) with any base font size, browse a table of common sizes and convert every px value in a CSS snippet at once. Free.

SVG to JSX Converter

Convert SVG markup into a clean React component online: camelCase attributes, className, style objects, props spread and optional TypeScript. Free & private.

SVG to CSS Converter

Turn SVG code into an optimized, URL-encoded data URI for CSS background-image or mask-image, with a Base64 option, cleanup and live preview. Free online.

CSS to Tailwind Converter

Convert CSS to Tailwind CSS classes online. Maps spacing, sizing, flexbox, grid, type, colours and borders to utilities, with arbitrary values.

Glassmorphism Generator

Generate frosted-glass CSS with backdrop-filter blur, saturation and transparency — with the -webkit- prefix Safari needs, a fallback and Tailwind classes.

Tailwind Arbitrary Value Generator

Convert CSS into exact Tailwind arbitrary value classes — grid-cols-[1fr_200px_auto], [clip-path:…], text-[clamp(…)] — with spaces and brackets escaped.

• No spaces — class names can’t contain spaces, so spaces become underscores — 1fr 200px auto → 1fr_200px_auto. Spaces after commas are simply removed.
• Type hints — some utilities are ambiguous with CSS variables (is text-[var(--x)] a color or a size?). The tool adds hints like text-[color:var(--brand)] or…
• !important — becomes the ! prefix.

SVG ViewBox Scaler

Resize an SVG viewBox and rescale every path, circle, rect and polygon coordinate proportionally — no transform wrappers. Normalize icons to 24×24 or any size.

Slider & Carousel Generator

Build a responsive image slider or carousel visually and copy the code. Swiper, Splide, Glide.js or Slick with autoplay, loop, effects and a live preview. Free.

Swiper Slider Generator

Generate Swiper.js slider code visually: slides per view, breakpoints, loop, autoplay, effects (fade, cube, coverflow) and navigation, with a live preview.

Splide Slider Generator

Create Splide.js carousels visually: perPage, gap, breakpoints, loop or fade, autoplay, arrows and pagination with a live preview. Copy CDN or npm code.

Glide.js Slider Generator

Generate Glide.js carousel code with a live preview: perView, gap, breakpoints, carousel or slider mode, autoplay, arrows and bullets. Tiny and dependency-free.

Slick Slider Generator

Generate Slick carousel code with a live preview: slidesToShow, responsive settings, infinite, autoplay, fade, center mode, arrows and dots, with jQuery.

Image Converter

Convert images between PNG, JPG, WebP and AVIF online. Batch convert, set quality, resize and download as ZIP. Runs in your browser — images are never uploaded.

Image Compressor

Compress JPEG, PNG and WebP images in your browser — batch upload, quality control, resize, convert to WebP and download as ZIP. Free, no upload.

• JPEG, WebP and AVIF — are lossy: the quality slider controls how much fine detail the encoder throws away. Dropping from 100 to about 80 usually removes a large share of…
• PNG — is lossless, so a quality setting does nothing. Instead, the tool reduces the image to a palette of at most 256 colors (8-bit PNG) using median-cut…
• Resizing — is often the biggest win: a 4000 px phone photo displayed in an 800 px column wastes most of its pixels. Set a max width/height and the image is…

QR Code Generator

Create free QR codes for URLs, Wi-Fi, vCards, email, phone and SMS. Custom colours, logo, error correction; download PNG or SVG. Static codes that never expire.

• Keep the quiet zone — The standard asks for a 4-module empty border; cropping it is a top cause of failed scans.
• Contrast and polarity — Dark modules on a light background work everywhere. Light-on-dark (inverted) codes fail in some scanner apps.
• Print size — As a rule of thumb, make the code at least 2 cm (0.8 in) wide, and about one-tenth of the expected scanning distance. Use SVG for print so it stays…

Favicon Generator

Create a favicon.ico, Apple touch icon, Android icons and site.webmanifest from an image, text or emoji. Copy the HTML, download a ZIP. Free, in-browser.

• Design for 16 px — Fine detail and long words disappear at tab size. A single bold letter, a simple mark or an emoji reads far better than a full logo with a tagline.
• Apple touch icons must be opaque — iOS rounds the corners itself and fills transparent pixels with black, so this tool always exports the 180 px icon (and the Webflow webclip) as a…
• Check dark mode — A dark logo on a transparent background vanishes in a dark browser tab — the preview shows both themes. Add a background color or padding if needed.

Placeholder Image Generator

Create placeholder images of any size with your text and colours. Download PNG, JPG, WebP or SVG, copy a data URI, or generate many sizes at once as a ZIP.

• SVG — a few hundred bytes at any size, perfect inline in HTML or as a data URI.
• PNG — exact colors and crisp text, for uploads that require a raster file.
• JPG / WebP — when a system only accepts photos or you need realistic file sizes for performance tests.

HEIC to PNG

Convert HEIC and HEIF photos from iPhone to lossless PNG — or JPG and WebP — in your browser. Batch conversion and ZIP download. Photos are never uploaded.

Image Resizer

Resize images online by pixels or percentage, keep the aspect ratio, crop to fill or fit with a background. Presets for Instagram, OG, X and YouTube. Free.

• Crop to fill — (like CSS object-fit: cover) scales the image until it covers the whole frame and trims the overflow. Use the crop focus to keep the top (faces,…
• Fit inside — (like object-fit: contain) shows the entire image and fills the empty bars with a background color — or transparency for PNG/WebP. Good for logos and…
• Stretch — forces the exact size and distorts the image; only use it when the ratio is already almost the same.

Image to Base64

Convert images to Base64 data URIs with ready-to-paste CSS and snippets, or decode Base64 back to an image. Free, private, runs in your browser.

• Good fit — small icons, loaders and UI sprites under a few KB, images in HTML email signatures where external images are blocked, single-file HTML reports, and…
• Bad fit — photos, hero images and anything above roughly 10–20 KB. Serve those as normal files with caching, compression and loading="lazy". Shrink them first…

OG Image Generator

Design 1200×630 Open Graph images from templates with auto-fitting titles, logo and photo. Download PNG or JPEG plus og: and twitter: meta tags. Free.

• Short, large text — Previews are often shown at around 500 px wide or smaller on phones. Aim for a title of 4–10 words; the auto-fit warns you when it has to truncate.
• Don’t repeat the URL bar — Platforms already show your domain and page title under the image, so use the image for the hook, not the full headline plus description.
• High contrast — Use the darkening slider on photos so white text stays readable, and test against both light and dark app themes.

PNG to JPG Converter

Convert PNG to JPG online for free. Batch convert, choose quality and the background color for transparent areas, and download as ZIP. Nothing is uploaded.

JPG to PNG Converter

Convert JPG to PNG online for free. Lossless output, batch conversion, optional resizing and ZIP download. Runs in your browser, so photos are never uploaded.

PNG to WebP Converter

Convert PNG to WebP online and cut file size by up to 80 % while keeping transparency. Batch convert, set quality and download as ZIP. Images stay private.

WebP to PNG Converter

Convert WebP to PNG online for free. Keeps transparency, converts many files at once and downloads them as ZIP. Works in your browser; nothing is uploaded.

JPG to WebP Converter

Convert JPG to WebP online: 25–35 % smaller files at the same visual quality. Batch convert, resize and download as ZIP. Runs locally in your browser.

WebP to JPG Converter

Convert WebP to JPG online for free. Choose quality and background color, convert many images at once and download as ZIP. No upload, no sign-up.

AVIF to PNG Converter

Convert AVIF to PNG online for free. Lossless output with transparency, batch conversion and ZIP download. Runs in your browser; nothing uploaded.

SVG to PNG Converter

Convert SVG to PNG online at any resolution with a transparent background. Set the width, batch convert and download as ZIP. Rendered in your browser.

HEIC to JPG

Convert iPhone HEIC photos to JPG, PNG or WebP in your browser. Batch convert, pick quality and size, download as ZIP. Private — photos are never uploaded.

Image Cropper

Crop images online with drag handles and exact pixel values: 1:1, 16:9, 4:5, social sizes or a circle. Export PNG, JPG or WebP. Free and private.

Rotate & Flip Image

Rotate images 90°, 180° or any angle and flip them horizontally or vertically — one photo or a whole batch. Download PNG, JPG or WebP. Runs in your browser.

• Rotate 90° / 180° — fixes photos that come out sideways or upside down. Rotation in 90° steps is lossless in pixels: nothing is cropped or blurred.
• Flip horizontal — mirrors left and right, e.g. to un-mirror a selfie or make a subject face into the page.
• Flip vertical — mirrors top and bottom, useful for reflections and some design effects.

Watermark Image

Add a text or logo watermark to photos in a batch: position, size, opacity, rotation and tiled patterns. Download JPG, PNG or WebP. Runs in your browser.

EXIF Viewer & Remover

View EXIF, GPS, XMP and IPTC metadata in photos — camera, settings, date and location — and remove it before sharing. Lossless for JPG, PNG and WebP.

Contrast Checker

Check colour contrast ratios against WCAG 2.2 AA and AAA for text and UI components, preview it live, see the APCA score and get the nearest passing colour.

Tailwind Color Generator

Generate a full Tailwind-style 50–950 color scale from one brand color. Export Tailwind v4 @theme, tailwind.config.js, CSS variables, SCSS or JSON. Free.

HEX to RGBA Converter

Convert HEX colors to RGBA with a live opacity slider and copy ready-to-use CSS: rgba(), modern rgb() with alpha, 8-digit HEX, HSLA and OKLCH. Free.

CSS Variables to Tailwind

Paste CSS custom properties and get a ready-to-paste tailwind.config.js colors object or a Tailwind v4 @theme block. Groups shades like brand-500 automatically.

OKLCH Color Converter

Pick colors in OKLCH with lightness, chroma and hue sliders and convert between OKLCH, HEX, RGB, HSL and OKLab — with sRGB gamut check and CSS fallbacks.

• Predictable palettes — in HSL, yellow at 50% lightness looks far brighter than blue at 50%. In OKLCH, changing only the hue keeps perceived lightness — great for generating…
• Better accessibility maths — a fixed lightness difference translates into a fairly consistent contrast difference.
• Wide-gamut colors — OKLCH can express Display P3 colors that HEX and rgb() cannot, so modern screens can show more vivid colors.

Color Name Finder

Find the name of any HEX color (e.g. #55AAEE = Cerulean) from 5,000 curated names and get ready-made CSS, SCSS, JS and Tailwind variable names. Free.

Color Mixer

Mix two colors and generate any number of in-between steps in OKLab, OKLCH, sRGB or HSL. Copy HEX values, CSS variables, color-mix() and gradient code.

APCA Contrast Checker

Check text contrast with APCA, the Accessible Perceptual Contrast Algorithm proposed for WCAG 3. Get the Lc value, use-case guidance and a WCAG 2 comparison.

• Polarity aware — WCAG 2 treats white-on-black and black-on-white identically, but our eyes don’t. APCA scores them differently.
• Better with dark mode — the WCAG 2 formula overstates contrast for dark color pairs, so some “passing” dark-theme combinations are hard to read. APCA catches these.
• Fewer false failures — some readable mid-tone pairs, such as white text on orange buttons, fail WCAG 2 while APCA rates them more realistically.

Color Blindness Simulator

Simulate protanopia, deuteranopia, tritanopia and achromatopsia on any image or palette to check your UI works for color-blind users. Runs in your browser.

• Never rely on color alone — (WCAG 1.4.1): add icons, labels, patterns or text to status messages, form errors and chart series.
• Vary lightness, not just hue — a dark green and a light red stay distinguishable for almost everyone. The OKLCH converter makes lightness easy to control.
• Use color-blind-safe chart palettes — such as blue/orange instead of red/green.

Color Converter

Free online color converter: turn HEX into RGB, HSL, HWB, OKLCH, CMYK and CSS color names, then generate a 50–950 tint & shade palette as CSS variables.

Bold Text Generator

Make bold, italic, monospace, script, underline and strikethrough text to paste into LinkedIn, Instagram, X and Facebook posts — and turn it back to plain text.

• Accessibility — screen readers often read these letters individually (“mathematical bold capital H…”) or skip them. Keep styled text to a few words and never style…
• Search — styled words aren’t matched by platform search or hashtags. Leave keywords, names and hashtags in plain text.
• Coverage — only A–Z, a–z and (for some styles) 0–9 have styled versions — accented letters such as ä or é stay unchanged.

Social Share Link Generator

Create share links for X, Facebook, LinkedIn, WhatsApp, Telegram, Reddit, Pinterest, Bluesky, Threads, XING and email — plus HTML and a dynamic Webflow script.

WhatsApp Link Generator

Create a wa.me click-to-chat link with your phone number and a pre-filled message, plus a QR code and button HTML for your website or Webflow site. Free.

• Website contact buttons — a “Chat on WhatsApp” button often converts better than a form on mobile.
• Instagram, TikTok and LinkedIn bios — one tap to start a conversation.
• Print — the QR code on flyers, menus, packaging or shop windows.

Social Media Character Counter

Check post length against the limits of X, LinkedIn, Instagram, Threads, Bluesky, TikTok, YouTube and more — with X’s weighted counting and “see more” cut-offs.

HubSpot Form Styler

Style embedded HubSpot forms visually: fonts, inputs, two-column fields, errors and buttons. Get the CSS and embed code, or copy a ready Code Embed to Webflow.

• Layout — full-width inputs, consistent spacing, and two- or three-column fieldsets rebuilt with flexbox (stacked on mobile).
• Inputs — text, email, select (with a custom arrow), textarea, checkboxes and radios with your accent color.
• States — focus ring, invalid fields and HubSpot’s error messages, with the “please complete all required fields” roll-up hidden.

Date Format Converter

Convert date format strings between Make, Zapier, Moment.js, n8n (Luxon), date-fns, Python strftime and PHP — with a live preview and a full token table.

• Make — {{formatDate(1.date; "DD.MM.YYYY")}}; to read a custom date string first use parseDate(1.text; "DD.MM.YYYY"). Make formats in the scenario’s time…
• Zapier — Formatter → Date/Time → Format, then pick or type the format in “To Format”. Set the time zone in the step to avoid off-by-one-day dates.
• n8n — {{ $json.date.toDateTime().toFormat('dd.MM.yyyy') }} or {{ $now.toFormat('yyyy-MM-dd') }}.

JSON Path Finder

Paste JSON, click any value and get its path for JavaScript, JSONPath, jq, Python, PHP, n8n and Make (1-based arrays) — perfect for webhook and API mappings.

Emoji Copy & Paste

Search 1,900+ emoji by name or keyword, pick skin tones, copy them and get the Unicode, HTML entity, CSS, JavaScript and shortcode — plus an emoji favicon.

Text Symbols & Special Characters

Copy and paste 1,200+ symbols: check marks, arrows, stars, bullets, math, currency, superscripts, box drawing, invisible spaces and kaomoji, with HTML codes.

ASCII Art Generator

Turn text into ASCII art banners in 20 FIGlet fonts. Preview all fonts at once, then copy plain, as a code comment, for a README or for the browser console.

• Code headers — a banner comment at the top of a stylesheet or the custom-code block of a Webflow site makes sections easy to find.
• README files — a logo in a Markdown code block renders on GitHub, npm and in terminals. Pair it with the README Generator.
• Console easter eggs — a console.log greeting in the browser dev tools, popular for hiring messages.

Unicode Character Inspector

Paste text to see every character’s name, code point, UTF-8 bytes and HTML code — and find and remove invisible zero-width spaces, BOMs and odd whitespace.

Base64 Encode / Decode

Encode text or files to Base64 and decode Base64 back to text online. Free, UTF-8 safe, supports URL-safe Base64 and data URIs. Runs entirely in your browser.

• Data URIs — inline small icons in CSS or HTML (see also the Image to Base64 tool).
• HTTP Basic Auth — the header is Basic + Base64 of user:password.
• JWTs — header and payload are Base64URL-encoded JSON; inspect them with the JWT Decoder.

UUID Generator

Generate random UUID v4 or time-ordered UUID v7 online, one or thousands at once. Free, secure and private. Also validates a UUID and decodes its timestamp.

URL Encode / Decode

Free online URL encoder and decoder. Percent-encode query strings with encodeURIComponent or encodeURI, decode URLs safely and parse query parameters.

Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and dates to epoch time. Free online converter with live epoch clock, seconds/ms auto-detection and time zones.

HTML Entity Encoder

Encode special characters to HTML entities or decode entities back to text. Free online HTML escape tool with named, decimal and hex entities and HTML5 support.

Password Generator

Generate strong passwords and passphrases: include or exclude words, pick allowed symbols, avoid sequences, start with a letter, bulk mode. All in your browser.

• Cryptographically secure randomness — Characters are picked with crypto.getRandomValues(), the browser's CSPRNG, using rejection sampling so every character is equally likely (no modulo…
• Nothing leaves your device — Passwords are generated in this page, are not sent to a server, not stored in local storage and never put in the URL. Only your settings (length,…
• “At least one of each type” — regenerates until every selected type appears, which keeps the result uniformly random among passwords that meet typical site rules.

Word Counter

Count words, characters, sentences and paragraphs as you type. See reading time, keyword density and limits for meta tags, X and Instagram. Free online.

• Words — are runs of characters separated by whitespace that contain at least one letter or digit, so “don't”, “e-mail” and “2026” each count as one word and…
• Characters — are counted as the symbols you see, so an emoji such as 👍🏽 or a flag counts as one character, not four code units.
• Sentences — end with ., ! or ? (common abbreviations such as “e.g.”, “Dr.” and “etc.” are ignored); a final sentence without punctuation still counts.

Password Strength Checker

Test how strong a password is: entropy, possible combinations, time to crack in four attack scenarios, weak patterns and a private data-breach check.

• Length beats complexity — Aim for 16+ random characters or a passphrase of 5–6 random words.
• Never reuse passwords — Breached passwords are tried on other sites (credential stuffing) — reuse is the biggest real-world risk.
• Use a password manager — and turn on two-factor authentication for important accounts.

Case Converter

Convert text to UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE instantly. Free & private.

Soft Hyphen Generator

Insert soft hyphens (&shy;) and zero-width spaces into long words so headlines break nicely on mobile. Auto mode for German & English, copy as text or HTML.

Smart Quotes to Straight Quotes

Fix code and JSON broken by curly “smart” quotes from Word, Slack or Docs. Converts them to straight quotes and cleans dashes, ellipses and hidden spaces.

Markdown Task List Converter

Turn any list into a GitHub-flavored Markdown task list (- [ ]), HTML checklist, Jira or CSV. Tick items in the preview and keep nesting — free checklist tool.

Markdown Editor

Free online Markdown editor with live preview, formatting toolbar, outline, word count and autosave. Export to .md, HTML or PDF. Runs in your browser.

Slug Generator

Turn titles into clean, SEO-friendly URL slugs. Transliterates accents and German umlauts, removes stop words, sets length and handles bulk lists. Free.

• Transliteration — Accented letters are mapped to their base letters (é → e, ñ → n, ç → c, ł → l), ligatures are expanded (æ → ae, œ → oe, ß → ss) and Cyrillic and…
• German umlauts — With the German option on, ä/ö/ü become ae/oe/ue — the spelling German readers expect (Größe → groesse, not grosse). Turn it off for other languages,…
• Clean-up — Apostrophes are dropped (what's → whats), & becomes “and” (or “und”/“et”), every other run of punctuation or whitespace becomes a single separator,…

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text by paragraphs, sentences, words or list items, with optional HTML tags. Plus plain-English filler. Free online.

• Realistic layouts — Wireframes and mock-ups look and behave like the real thing — line lengths, wrapping and paragraph rhythm are visible early.
• Focus on design — Stakeholders review the layout instead of editing copy that isn't final.
• Testing — Developers fill templates, CMS fields and components with varying lengths to catch overflow, truncation and empty-state bugs.

Remove Duplicate Lines

Remove duplicate lines from any list online, case-insensitive or trimmed, then sort A–Z, numerically, by length or shuffle. Shows counts. Free and private.

• A → Z / Z → A — sorts alphabetically using your browser's locale-aware collation, so accented letters sort next to their base letters (é with e).
• Natural — sorts numbers inside text by value: file2, file10, file100 instead of the plain alphabetical file10, file100, file2.
• By length — orders lines from shortest to longest (or the reverse), handy for finding outliers.

Possibility & Combination Calculator

How many possibilities? Combinations (nCr) and permutations (nPr), with or without repetition, lottery odds and PIN/code possibilities — exact values.

• Lotto 6 of 49 — C(49, 6) = 13,983,816 — the odds of the jackpot are 1 in about 14 million.
• Poker hands — C(52, 5) = 2,598,960 different 5-card hands.
• 4-digit PIN — 10⁴ = 10,000 possibilities (order matters, digits repeat).

Random Number Generator

Random numbers in any range, random name picker, team generator, coin flip and dice roller — fair, crypto-secure randomness right in your browser.

• Random numbers — any range, up to 10,000 at once, unique or with repeats, optionally sorted. Great for raffles, sampling and testing.
• Random name picker — paste participants and draw one or several winners for a giveaway, or shuffle the order of speakers.
• Team generator — split a class, workshop or five-a-side group into balanced random teams.

Age Calculator

Calculate exact age in years, months and days from a date of birth — plus total days and weeks, the weekday you were born, next birthday and star sign.

• Leap-day birthdays — (29 February): in non-leap years the birthday is usually celebrated on 28 February or 1 March; legally it depends on the country.
• Age on a specific date — is useful for eligibility checks — school entry, insurance, competitions or retirement dates.

Percentage Calculator

Free percentage calculator: find X% of Y, what percent one number is of another, percentage change, increase or decrease by a percent and reverse percentages.

• Reversing a discount — a price that rose 20% doesn’t return to the original after a 20% cut — 100 → 120 → 96. To undo a 20% increase, divide by 1.2 (that’s what the reverse…
• Removing VAT or sales tax — to get the net price from a gross price including 19% VAT, divide by 1.19 — don’t subtract 19%. 119 ÷ 1.19 = 100, while 119 − 19% = 96.39.
• Percent vs percentage points — a conversion rate moving from 2% to 3% is a rise of 1 percentage point, but a 50% relative increase.

Date Difference Calculator

Calculate the days between two dates with a years, months and weeks breakdown and business days. Add or subtract days or count down to an event. Free.

Time Zone Converter

Convert a date and time between any time zones with DST handled automatically. Compare cities side by side and find meeting times within 9–5 working hours.

Unit Converter

Free unit converter for length, weight, temperature, area, volume, speed, data size (KB vs KiB), time, energy and pressure — instant, two-way, with full tables.

Aspect Ratio Calculator

Calculate width or height for any aspect ratio, simplify pixel sizes to a ratio like 16:9 and get CSS aspect-ratio and padding-top values. Free online tool.

• New height — = new width × ratio height ÷ ratio width — e.g. 1280 × 9 ÷ 16 = 720.
• New width — = new height × ratio width ÷ ratio height — e.g. 1080 × 16 ÷ 9 = 1920.
• Simplify a size — divide both sides by their greatest common divisor (GCD). 1920 and 1080 share a GCD of 120, giving 16:9.

Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any base 2–36 — with big-number support, two’s complement bit view and text to hex/binary. Free.