Screen Resolution Checker

What the Screen Resolution Checker does

The Screen Resolution Checker instantly displays your screen's resolution, browser viewport size, and device pixel ratio — the exact numbers designers and developers need for responsive design work.

How to use it

1. The page automatically detects and displays your screen resolution, viewport size, and pixel ratio.
2. Click Refresh after resizing your browser window to update the figures.

Common uses

• Checking your exact viewport size while testing a responsive website design.
• Confirming a device's pixel ratio for exporting correctly sized image assets.
• Reporting your screen resolution to a support technician for troubleshooting.
• Verifying how a specific screen size renders a layout before launch.
• Checking resolution details when configuring a display or projector setup.

Good to know

Screen resolution (the display's total pixel dimensions) and viewport size (the actual visible browser window area) are two different numbers — the viewport is usually smaller since it excludes the OS taskbar, browser chrome, and any other on-screen elements, which matters when you're designing specifically for viewport dimensions rather than full screen resolution.

The gap between screen resolution and viewport size has grown more pronounced as high-DPI ("Retina") displays have become standard — a display might report a physical resolution far higher than the effective viewport size that web content actually renders at, because the operating system scales content up for readability, which is exactly why the pixel ratio figure matters alongside the raw resolution number.