Developer

Browser Window Size Checker

Use a browser window size checker to inspect live viewport dimensions, outer window size, and device pixel ratio while resizing the browser.

Browser window size checker

Resize the browser window to see live viewport and window dimensions update instantly.

This checker is useful when you are testing responsive breakpoints, comparing browser chrome against the visible viewport, or confirming the live innerWidth and innerHeight values reported by the browser.

Live window metrics

Current browser window and viewport values.

Viewport
0 x 0
Outer window
0 x 0
Visual viewport
0 x 0
Device pixel ratio
1
Orientation
portrait
Viewport: 0 x 0
Outer window: 0 x 0
Visual viewport: 0 x 0
Device pixel ratio: 1
Orientation: portrait

Why use a browser window size checker

A browser window size checker helps you inspect the live viewport and outer browser dimensions while you resize the page. It is useful when you are testing responsive layouts, debugging media queries, or confirming the dimensions a browser reports at a given breakpoint.

That makes the page useful for searches like browser window size checker, window size checker, viewport size checker, browser window dimensions checker, innerWidth checker, and browser dimensions checker because it shows the live values directly in the browser.

Check viewport size and browser window size together

The browser window size checker shows the viewport width and height, the outer window size, the visual viewport size, and the current device pixel ratio. That combination makes it easier to compare what the page can actually render against the browser chrome around it.

This is useful when you want to confirm responsive behavior, inspect scrollbars, verify browser zoom behavior, or check the live innerWidth and innerHeight values on desktop and mobile.

Common browser window size checker use cases

Use this page when you are tuning breakpoints, testing a design handoff, verifying browser zoom behavior, or checking whether a layout fits within the available window space. It is also helpful when you need a quick browser window size checker without opening developer tools or a separate viewport size checker.

Because the values update live, you can resize the browser and immediately see how the reported window size changes, which makes it a practical responsive design checker.

FAQ

What does a browser window size checker show?

It shows the current viewport dimensions, outer browser dimensions, visual viewport size, device pixel ratio, and orientation.

Does it update when I resize the window?

Yes. The values update live as the browser window changes size.

Is this the same as screen resolution?

No. This tool focuses on the browser window and viewport, while screen resolution detection focuses on the display itself.

Does it work locally?

Yes. The tool reads window metrics in the browser and does not send anything to a server.

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