How to use the package.json Generator
- Enter the package name and version — the name is checked against npm’s naming rules as you type.
- Choose a scripts preset (Node, Vite, Next.js, TypeScript library) and the module type.
- Add license, author, repository and the Node.js version your code needs.
- Copy or download the file into your project root, then run
npm installto add dependencies.
The most important package.json fields
| Field | What it does |
|---|---|
name | Package name — lowercase, max. 214 characters, URL-safe, may be scoped (@org/name) |
version | A semantic version like 1.4.2 |
type | "module" treats .js files as ES modules (import); default is CommonJS |
main / exports | The entry point(s) other code imports. exports also hides internal files |
scripts | Commands for npm run dev, build, test… |
engines | Node.js versions your code supports |
private | true prevents accidental npm publish |
packageManager | Pins npm, pnpm or Yarn via Corepack |
Dependencies are added by the package manager
Don’t type dependency versions by hand — run npm install react or npm install -D vite and npm writes them with the right version range (usually ^). Commit the lock file so everyone installs the same versions.
Next steps for a new project
Add a .gitignore (at least node_modules/ and .env), an .editorconfig, a README and a GitHub Actions workflow that runs your test and build scripts on every push.
Tools that pair well with the package.json Generator
- JSON Formatter — Paste JSON to pretty-print, minify or validate it.
- Git Command Generator — Pick a task like “undo the last commit but keep my changes” or “rename a branch on GitHub”, fill in your branch names and get the exact Git commands — each line explained, risky steps flagged.
- .env File Validator — Paste a .env file to find invalid keys, duplicates, empty values and quoting mistakes, compare it with .env.example to spot missing variables, and generate a safe example file.
- Changelog Generator — Paste your git log and get a tidy CHANGELOG.md section: commits grouped into Features, Bug Fixes, Performance and Breaking Changes, scopes in bold, links to commits — plus the next semantic version.
Frequently asked questions
What are the rules for npm package names?
Lowercase only, no spaces, max. 214 characters, can’t start with a dot or underscore, only URL-safe characters (letters, digits, - . _ ~), and not a Node.js core module name like http. Scoped names look like @scope/name.
Should I use "type": "module"?
For new projects, yes — ES modules are the standard and work in Node.js 18+, Vite and most tools. Use CommonJS only if you depend on tooling that requires require().
What does "private": true do?
It makes npm refuse to publish the package, which protects apps and internal projects from being published by accident.
Where do dependencies go?
Install them with npm, pnpm or Yarn; the tool writes them into dependencies or devDependencies automatically.