What is my screen resolution? Check it in one glance
The Screen Resolution Checker reads your display’s details straight from the browser: the screen resolution in CSS pixels, the physical pixel count after scaling, the live browser viewport size, the available screen area without the taskbar, the device pixel ratio, colour depth, colour gamut and HDR support, orientation and an estimate of the refresh rate. Add your screen’s diagonal size and it calculates the pixel density in PPI and the real picture dimensions.
It is useful for web designers checking breakpoints, for support staff asking “what resolution are you on?”, for gamers and photographers comparing monitors, and for anyone deciding whether the Windows or macOS scaling is set the way they think it is. Resize the browser window and the viewport numbers update as you drag.
Everything comes from your own browser’s screen and window properties — nothing is uploaded, and the copy button gives you a plain-text report to paste into a ticket or chat.
How to use the Screen Resolution Checker
- Open the page: your screen resolution appears at the top with its common name, such as Full HD or 4K UHD, when there is one.
- Read the cards for physical pixels, live viewport, available area, pixel ratio, colour depth, orientation, aspect ratio and refresh rate.
- Type your screen’s diagonal in inches (or pick a common size) to see the pixel density in PPI, the dot pitch and the picture’s width and height in centimetres.
- Resize or rotate the browser and watch the viewport and orientation values update live.
- Press Copy report to copy every value as text.
Screen Resolution Checker features
CSS and physical pixels side by side
Shows the logical resolution the browser sees and the real pixel count after scaling (CSS pixels × device pixel ratio).
Live viewport size
The inner window size updates as you resize, which is exactly what CSS media queries respond to.
Resolution names
Recognises HD, Full HD, QHD, 4K UHD, ultrawide formats and scaled laptop resolutions such as 1536 × 864.
PPI calculator
Enter the diagonal and get physical PPI, CSS pixels per inch, dot pitch in millimetres and the picture size in inches and centimetres.
Colour and HDR details
Colour depth, sRGB / Display P3 / Rec. 2020 gamut and HDR support via media queries, plus touch points and pointer type.
Copy-ready report
One click copies a clean multi-line report including the browser’s user agent for support requests.
CSS pixels, physical pixels and the device pixel ratio
Browsers report sizes in CSS pixels, which are scaled units, not hardware pixels. A 1920 × 1080 laptop set to 125 % scaling in Windows reports a screen of 1536 × 864 CSS pixels with a device pixel ratio of 1.25; a phone with a 1170 × 2532 panel reports 390 × 844 at 3×. Multiply the CSS size by the ratio to get the physical pixels, which is what the monitor’s box advertises. If the numbers look “wrong”, scaling is almost always why — change it under Settings → System → Display (Windows) or System Settings → Displays (macOS).
The viewport is the part of the browser window that shows the page, excluding tabs and toolbars; it is what responsive design breakpoints such as 768 px or 1024 px refer to. Available screen area excludes the taskbar or dock. Browser zoom changes the pixel ratio too: at 150 % zoom a 1× screen reports 1.5×.
Common screen resolutions and their names
| Name | Resolution | Aspect ratio | Typical devices |
|---|---|---|---|
| HD (720p) | 1280 × 720 | 16:9 | Budget TVs, projectors |
| HD / WXGA | 1366 × 768 | 16:9 | Budget laptops |
| Full HD (1080p) | 1920 × 1080 | 16:9 | Most monitors, laptops and TVs |
| WUXGA | 1920 × 1200 | 16:10 | Business laptops, 24″ monitors |
| QHD / 1440p | 2560 × 1440 | 16:9 | 27″ gaming and office monitors |
| UWQHD | 3440 × 1440 | 21:9 | 34″ ultrawide monitors |
| 4K UHD (2160p) | 3840 × 2160 | 16:9 | 4K TVs and monitors |
| 5K | 5120 × 2880 | 16:9 | 27″ Apple and LG displays |
| 8K UHD | 7680 × 4320 | 16:9 | High-end TVs |
How PPI is calculated and what counts as sharp
Pixels per inch = diagonal resolution in pixels ÷ diagonal size in inches. For a 27-inch 2560 × 1440 monitor: √(2560² + 1440²) = 2937 pixels, and 2937 ÷ 27 ≈ 109 PPI. A 15.6-inch Full HD laptop is about 141 PPI, a 6.1-inch phone at 1170 × 2532 is around 460 PPI. Above roughly 200 PPI, individual pixels disappear at normal laptop viewing distance; desktop monitors look sharp from 110 PPI upward because they sit farther away. The calculator uses your physical pixel count, so it stays correct whatever scaling is applied.
For precise pixel maths in design work, try the px to rem Converter and the Aspect Ratio Calculator; to check the panel’s motion and health use the Refresh Rate Test and Dead Pixel Test.
Screen Resolution Checker FAQ
Why does the checker show a lower resolution than my monitor?
Because the browser reports CSS pixels after display scaling. A 4K monitor at 150 % scaling shows 2560 × 1440 with a pixel ratio of 1.5. The “Physical pixels” card multiplies the two back to your real 3840 × 2160.
What is the difference between screen resolution and viewport size?
Screen resolution is the whole display. The viewport is only the area inside the browser window where the page is drawn, so it is smaller and changes when you resize the window or open developer tools.
How do I find my screen’s diagonal size for the PPI calculator?
It is usually in the model name or on a label on the back (for example 24″ or 15.6″). Otherwise measure corner to corner across the visible image, not the bezel, with a tape measure in inches.
Is the refresh rate value exact?
It is a quick one-second estimate from the browser’s animation timing, snapped to a standard rate when close. For a longer, more reliable measurement with a frame-time graph, use the dedicated Refresh Rate Test.
Can I use this on my phone?
Yes. Phones report their scaled CSS resolution (for example 390 × 844) with a pixel ratio of 2 or 3; the physical pixel card shows the true panel resolution. Rotate the phone to see the orientation update.
Does the page collect my screen information?
No. The values are read by JavaScript in your browser and displayed only to you. Nothing is sent to a server; the copy button just puts the text on your clipboard.