User Agent Parser

A user agent is a line of text a browser sends with every request to identify itself. It packs together the browser name and version, the rendering engine, the operating system and version, and device hints. The format is historically messy — almost every browser still starts with the word Mozilla — which is why a parser is handy for pulling out the parts that matter.

It reads the string with pattern rules, checking for the tokens that identify each browser, engine and OS — such as Edg for Edge, CriOS/Chrome for Chrome, Firefox for Firefox, Version+Safari for Safari, plus Windows NT, Mac OS X, Android and iPhone OS markers. Order matters — Chrome-based browsers also contain "Safari", so specific browsers are tested first. It runs entirely in your browser.

It's a good hint, not a guarantee. User agents can be changed, spoofed or frozen — modern browsers reduce the detail they report for privacy, so exact versions are less available. For real feature support, feature detection in code beats parsing the UA. This tool is best for identifying a visitor, debugging, or seeing what your own browser reports.

No. Your user agent is read from your browser and parsed entirely on your device — nothing is uploaded, logged or stored. You can paste any other UA string to parse it too, which is useful for debugging a log entry. There is no sign-up, and it works offline once loaded.