Screen Resolution Checker

Check your screen resolution and browser viewport size free online. See display dimensions, pixel ratio, color depth, and browser window size instantly.

Read directly from your browser -- nothing sent anywhere.

How to Use This Tool

Load the pageInformation displays automatically, no action needed

Resize if neededViewport values update live as you resize the window

Use the numbersReference for responsive design testing or troubleshooting

The Numbers Behind "Why Does This Look Different on My Screen"

A layout that looks perfect on a designer's monitor can look cramped or oddly spaced on someone else's device, and the reason almost always traces back to differences in screen resolution, viewport size, or pixel density between the two setups. Having quick access to these exact numbers removes the guesswork from diagnosing display-related issues.

Resolution Versus Viewport -- A Distinction Worth Knowing

Your monitor might be 1920x1080 pixels, but the actual visible browser content area (the viewport) is smaller once browser toolbars, tabs, and any taskbar space are subtracted. Responsive web design specifically targets viewport dimensions, not raw screen resolution, since that's the actual space available for content.

Device Pixel Ratio and Crisp Images

A device pixel ratio of 2 means the display packs twice as many physical pixels into the same CSS pixel space compared to a ratio of 1. Images designed at standard resolution will appear soft or blurry on these higher-density displays unless served at the appropriate doubled resolution -- a common reason "why do my images look slightly blurry" issues happen specifically on newer high-end devices.

Frequently Asked Questions

Screen resolution is your monitor's total physical pixel dimensions, while viewport size is the actual visible browser window area, which is smaller once you account for browser chrome (toolbars, tabs), taskbars, and any portion of the screen not covered by the maximized browser window.

It indicates how many physical screen pixels correspond to one CSS pixel -- a ratio of 2 (common on Retina-style displays) means images and elements need to be designed at double resolution to appear crisp rather than blurry on that display.

Responsive design testing, debugging layout issues that only appear at specific resolutions, and verifying that retina-resolution image assets are being served correctly to high-DPI displays all require knowing the actual numbers for the device being tested.

Most modern displays support 24-bit color (16.7 million colors) as a practical standard, so checking this matters less than it once did, though it's occasionally relevant for verifying specialized professional display setups.

Viewport-related values update live as you resize the window, since viewport size is dynamic by nature. Screen resolution itself stays fixed since it reflects the monitor's actual hardware capability, not the current window size.