Screen Resolution Test
Everything about your screen in one place: resolution, viewport, pixel ratio, colour depth and more.
How to Use the Screen Resolution Test
This page reads what your browser knows about your display. The screen resolution is in CSS pixels. Multiply by the device pixel ratio to get the real, physical pixels. Handy for web design, support tickets and checking that Windows scaling is set the way you want.
- Open the page. Results appear instantly.
- Check the resolution. Compare with your monitor's native resolution.
- Resize the window. The viewport updates live.
- Copy the results. Paste them into a support ticket.
Why Is My Resolution Lower Than My Monitor?
Windows and macOS scale the desktop so text is readable. A 4K screen at 150% scaling reports 2560 × 1440 CSS pixels with a pixel ratio of 1.5. The physical resolution line shows the real number.
Common Resolutions
| Name | Pixels |
|---|---|
| HD | 1280 × 720 |
| Full HD | 1920 × 1080 |
| QHD / 1440p | 2560 × 1440 |
| Ultrawide | 3440 × 1440 |
| 4K UHD | 3840 × 2160 |
Frequently Asked Questions
Is my data sent anywhere?
No. It is shown only to you.
What is device pixel ratio?
How many real pixels make one CSS pixel. 2× is common on phones and Retina screens.
Why does HDR say No?
HDR may be off in Windows, or the browser does not report it.
Can I check my phone?
Yes.
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