🖥️ What Is My Screen Resolution
Instantly see your screen resolution, the real physical pixels behind Windows or Mac scaling, your browser viewport, aspect ratio, color depth and HDR.
Detecting your screen…
What What Is My Screen Resolution Does
This page shows your screen resolution the instant it loads, then explains the number. Browsers report resolution in CSS pixels — the layout units websites use — so a laptop with a 3840 × 2160 panel running at 150% scaling reports 2560 × 1440. Multiplying by the device pixel ratio gives back the physical pixels your display settings and the monitor box quote, and the page does that for you.
Alongside the headline number you get the browser viewport (the area actually available to a page), the available screen area without the taskbar or dock, the aspect ratio, color depth, whether the display reports a wide color gamut or HDR, and the number of touch points. Everything updates live as you resize the window, zoom or rotate a phone.
How to Use What Is My Screen Resolution
- Open the page — your resolution appears instantly
- Read the physical pixels and device pixel ratio behind any scaling
- Compare the browser viewport with the full screen size
- Check aspect ratio, color depth, color gamut and HDR support
- Copy the details to share with support or a developer
Formula Used by What Is My Screen Resolution
Physical pixels
Physical resolution ≈ CSS resolution × device pixel ratio
Worked example
A laptop reporting 1536 × 864 with a device pixel ratio of 1.25.
- 1536 × 1.25 = 1920
- 864 × 1.25 = 1080
Result: A 1920 × 1080 (Full HD) panel at 125% scaling.
Common Screen Resolutions
| Name | Resolution | Aspect ratio |
|---|---|---|
| HD / 720p | 1280 × 720 | 16:9 |
| WXGA | 1366 × 768 | ≈ 16:9 |
| Full HD / 1080p | 1920 × 1080 | 16:9 |
| WUXGA | 1920 × 1200 | 16:10 |
| QHD / 1440p | 2560 × 1440 | 16:9 |
| Ultrawide QHD | 3440 × 1440 | ≈ 21:9 |
| 4K UHD | 3840 × 2160 | 16:9 |
| 5K | 5120 × 2880 | 16:9 |
| 8K UHD | 7680 × 4320 | 16:9 |
Source: Display resolution — Wikipedia
How to Read Your Result
Why websites see a “smaller” screen
High-density displays pack more pixels into the same space, so the operating system scales everything up to keep text readable. Websites lay out in CSS pixels, which is why a phone with a 1170-pixel-wide panel is treated as about 390 pixels wide. Designers should test with the CSS size; photographers and gamers usually care about the physical one.
Zoom changes the numbers
Browser zoom multiplies the device pixel ratio and shrinks the CSS resolution. At 200% zoom a 1920 × 1080 screen reports 960 × 540. If the result looks wrong, press Ctrl + 0 (⌘ + 0 on a Mac) to reset zoom.
Limitations & Accuracy Notes
- Physical pixels are estimated from the device pixel ratio, which some browsers round; unusual scaling settings can be off by a pixel or two.
- With several monitors, the browser reports the screen the window is currently on.
- Color gamut and HDR reflect what the browser and operating system report, not a hardware measurement.