So nutzt du: What Is My Screen Resolution
- Open the page — the values appear immediately.
- Resize the window or rotate your phone to see the viewport change.
- Copy the details to share them in a bug report.
Screen resolution vs viewport
- 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.
Common screen sizes
| Device type | CSS viewport | DPR |
|---|---|---|
| Modern iPhone | 390–430 × 844–932 | 3 |
| Android phone | 360–412 × 780–915 | 2.6–3.5 |
| iPad | 768–1032 × 1024–1376 | 2 |
| Laptop | 1280–1536 × 720–960 | 1–2 |
| Full HD monitor | 1920 × 1080 | 1 |
| 4K monitor (scaled) | 1920–2560 × 1080–1440 | 1.5–2 |
Why the numbers look “wrong”
Operating systems scale the display: a 4K screen at 150 % scaling reports 2560 × 1440 CSS pixels with DPR 1.5. Browser zoom changes the DPR too — zoom to 200 % and the viewport halves. That is expected behavior, not an error.
For developers
Design with CSS pixels and test the common viewport widths (360, 390, 768, 1024, 1280, 1536). Serve sharp images to high-DPR screens with srcset and resize them with the image resizer. Fluid typography with the clamp() calculator avoids breakpoints for font sizes altogether.
Auch gesucht als: my screen resolution, screen size, viewport size, what is my resolution, device pixel ratio, browser window size, screen resolution checker.
Passende Tools zu: What Is My Screen Resolution
- Wie lautet meine IP-Adresse? — Deine öffentliche IP-Adresse und alles, was dein Browser den von dir besuchten Websites preisgibt – User-Agent, Bildschirmauflösung, Sprache, Zeitzone und Request-Header.
- User Agent Parser — Decode any User-Agent string into browser, engine, operating system and device — and find out whether it belongs to a search engine, AI crawler or script.
- Aspect Ratio Calculator — Resize images and videos without distortion: fill in a ratio and one side to get the other, or enter a size to find its ratio — with ready-to-paste CSS.
- PX to REM Converter — Convert between pixels, rem and em with your own root font size — or paste a whole stylesheet and convert every px value in one go.
Häufige Fragen
Why does my 4K monitor show a smaller resolution?
Display scaling: Windows and macOS enlarge everything, so the browser reports the scaled size in CSS pixels. Multiply by the device pixel ratio for the physical resolution.
What is the difference between screen size and viewport?
The viewport excludes the browser’s toolbars, tabs and window borders — it is the space the web page actually gets.
Is this information sent anywhere?
No. It is read by your browser and shown on this page only.
Kann ich What Is My Screen Resolution als Web-App installieren und offline nutzen?
Ja. What Is My Screen Resolution ist eine installierbare Web-App (PWA) – sie wird über Ihren Browser installiert und nicht aus einem App-Store heruntergeladen. Klicken Sie oben auf dieser Seite in Chrome oder Edge (Windows, macOS, Linux, ChromeOS) auf „App installieren“ oder verwenden Sie auf Android-Geräten „Teilen“ → „Zum Startbildschirm hinzufügen“ auf dem iPhone und iPad bzw. „Datei“ → „Zum Dock hinzufügen“ in Safari 17+ auf einem Mac. Die App öffnet sich dann in einem eigenen Fenster mit einem eigenen Symbol, und da sie vollständig in Ihrem Browser ausgeführt wird, funktioniert sie auch offline. Firefox auf dem Desktop kann keine Web-Apps installieren. So funktioniert die Installation.