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Your display's numbers, live: the big figure is the native panel resolution (physical pixels), alongside the CSS resolution websites actually see, your current browser viewport (resize the window and watch it change), and the device pixel ratio that links them. Useful for support tickets, CSS debugging, buying decisions and "will my design fit" sanity checks.
Frequently asked questions
Why does my 4K monitor show a smaller resolution?
Display scaling. At 150% scaling, a 3840×2160 panel reports 2560×1440 CSS pixels — each CSS pixel maps to 1.5 physical pixels (the pixel ratio). Both numbers are correct; they measure different things, which is why we show both.
What's the difference between screen resolution and viewport?
Resolution is the whole display; the viewport is just your browser window's content area — what websites can actually use. Web design decisions should target viewports, which is why this page shows yours updating live.
What resolution do most people have?
1920×1080 remains the most common desktop CSS resolution worldwide, with 2560×1440 growing and 390×844-ish dominating phones. Design for ranges, not a single number.