Screen Resolution Checker: What is My Screen Resolution?

Instantly detect your native screen resolution, browser viewport size, display scaling, and calculate your monitor's physical dimensions. This free online screen resolution tester works on any laptop, desktop, tablet, or phone.

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Free Online Screen Resolution Tester

Wondering what is my screen resolution? Our screen resolution checker reads your display the moment the page loads, so you can see your screen size in pixels without installing anything. Whether you need a quick screen resolution finder for a support ticket, want to confirm your monitor is running at its native 1920 × 1080 or 4K resolution, or you are testing responsive designs, this tool gives you the exact numbers instantly.

What this screen size checker detects

  • Native screen resolution — your monitor's true physical pixel count (width × height).
  • Browser viewport size — the usable area where web pages render.
  • Screen DPI and pixel ratio — your device pixel ratio and UI scaling factor for a fast monitor DPI check.
  • Color depth and aspect ratio — such as 16:9 widescreen, plus a PPI calculator for physical size in inches.

Frequently Asked Questions

To find out exactly screen resolution for your laptop, mobile, tv or any device, simply look at the detection tool at the top of this page. Screen resolution is the total number of physical pixels your monitor can display, usually expressed as width by height (e.g., 1920 × 1080). Our tool instantly calculates both your logical (CSS) pixels and your true physical native hardware pixels.

Screen Resolution is the total number of physical pixels your monitor has. Viewport Size is the inner dimensions of your browser window where websites are rendered. If your browser is not full screen, or if you have toolbars open, your viewport will be smaller than your screen resolution.

This is usually caused by UI Scaling (also known as DPI scaling). Operating systems like Windows and macOS scale up interfaces on high-resolution monitors so text isn't too small to read. Our tool detects both your Logical (scaled) resolution and your Native (physical) resolution.

Browsers cannot automatically detect the physical size of your monitor for privacy reasons. However, if you know the diagonal size (e.g., 27 inches), you can enter it into our PPI Calculator on this page to instantly determine your exact physical width and height.

This screen resolution checker shows your screen size in pixels automatically at the top of the page. The first number is the width and the second is the height, for example 1920 × 1080. No download or app is required, it works instantly in your browser on any device.

Yes. This is a completely free online screen resolution tester that reads the resolution values reported by your browser and operating system. It accurately reflects the resolution your device is currently using, including any display scaling, so the results match what your screen is actually rendering right now.

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