Why is my viewport smaller than my screen resolution?

Screen size is the whole display in CSS pixels. The viewport is only the area the page can draw in, so browser chrome and scrollbars come off it, along with any OS dock. Both figures are also divided by the device pixel ratio, which is why a 3840-pixel-wide monitor at 200% scaling reports 1920. The “viewport in device pixels” row multiplies it back for you.

Why does my iPad report macOS?

Safari on iPad sends a desktop user agent by default, so any string-based guess lands on Mac. The touch-points row is the reliable tell: a Mac reports zero, an iPad reports five. It is a neat demonstration of why user-agent sniffing is a poor basis for a feature decision.

Browser Info: What Any Site Can Read About You

How it works

Browser Info: What Any Site Can Read About You

Everything your browser tells a website about this device, read live and displayed here. Resize the window and the viewport figures follow along.

What this does

Viewport size next to the full screen and the available screen, updating as you resize
Pixel ratio and colour depth, plus the viewport converted into real device pixels
Browser, engine, operating system and version numbers parsed out of the user agent
Language list, timezone, UTC offset, cookie state, touch points, CPU threads and Do Not Track
Copy report puts every value plus the full user-agent string on the clipboard

FAQ

More than most people expect. The exact combination of screen size, pixel ratio, timezone, language list, CPU thread count and device memory is often unique to one machine, which is enough to recognise a browser again with no cookie involved. Every value on this page comes from an API that any page you visit can call without asking. The page reads them and prints them; nothing is sent. Treat it as a mirror of what you already give away rather than as another site collecting it.

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