ToolBox

DEVELOPER TOOL

Screen Resolution & Device Info

See your screen resolution, viewport size, browser, and device details.

About this tool

Shows your screen resolution, browser viewport size, pixel density, and other device details your browser exposes — useful for bug reports, responsive design testing, or just satisfying curiosity about your setup. The viewport size updates live if you resize the window.

Frequently asked questions

What's the difference between screen resolution and viewport size?
Screen resolution is your monitor's total pixel dimensions. Viewport size is how much of that is actually available to the browser window's content area, which is usually smaller once you account for the browser's own UI, other windows, or a non-maximized window.
What does device pixel ratio mean?
It's the ratio between physical device pixels and CSS pixels — a ratio of 2 (common on high-DPI "Retina" displays) means each CSS pixel is rendered using a 2×2 block of physical pixels for sharper detail.
Is any of this information sent anywhere?
No — everything here is read directly from your browser's own APIs and displayed locally; nothing is transmitted or logged.
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