Screen Resolution Checker
See your screen resolution instantly, plus the physical pixel count, device pixel ratio, aspect ratio, browser window size, estimated refresh rate (Hz), colour depth and HDR support. Values update live when you resize the window or rotate your phone.
This tool runs entirely in your browser.
How to use the Screen Resolution Checker
- 1Open the page — your resolution is shown at the top straight away.
- 2Resize the window or rotate your device to watch the viewport values update.
- 3Click “Copy all details” to paste the information into a support request.
What is the Screen Resolution Checker?
Websites see your screen in CSS pixels, which are scaled by your operating system’s display scaling and by browser zoom. A 4K laptop panel at 200 % scaling therefore reports 1920 × 1080; multiplying by the device pixel ratio gives the physical pixels, which is usually the panel’s native resolution. At 100 % browser zoom (Ctrl/⌘ + 0) the estimate is most accurate.
The viewport is the part of the browser window that shows the page — the size that matters for responsive web design. The refresh rate is estimated from the browser’s animation frames and rounded to common values such as 60, 120 or 144 Hz; battery saver, background tabs and some browsers cap animations, so a 120 Hz screen can measure as 60 Hz.
Frequently asked questions
Why is the resolution lower than my monitor’s specification?
Display scaling makes everything bigger and reduces the number of CSS pixels the browser reports. Check the “Physical pixels” row, or set scaling to 100 % in your system settings.
Why does my 144 Hz monitor show 60 Hz?
Make sure the monitor is set to 144 Hz in your display settings, the cable supports it, and the browser window is on that monitor. Some browsers also limit animations to 60 fps when on battery.
Can a website see my physical screen size in inches?
No. Browsers don’t expose the physical size of the display, only pixel counts, so inches can’t be measured from a web page.
Is the Screen Resolution Checker free and private?
Yes. The Screen Resolution Checker is free, needs no account, and runs entirely in your browser. What you type is never sent to a server or stored.
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