UsefulTab
User-Agent Parser
Decode a User-Agent into browser, engine, OS, and device.
Paste a User-Agent, or detect your own
Your browser's own User-Agent is prefilled. Edit it or paste a different string to see the browser, rendering engine, operating system, CPU, and device type it describes — all parsed locally with a dependency-free heuristic.
Runs entirely in your browserDecode a User-Agent string locally
Every browser sends a User-Agent string that names, in a famously tangled format, the browser, its rendering engine, the operating system, and often the CPU and device type. This tool prefills your own browser's User-Agent (from navigator.userAgent) and lets you paste any other string to decode. A small, dependency-free heuristic matches the usual brand tokens — Chrome, Edge, Firefox, Safari, Opera, Samsung Internet — the engines Blink, Gecko, and WebKit, and operating systems from Windows to iOS, Android, macOS, and Linux. Because User-Agent strings are self-reported, they can be spoofed, frozen, or trimmed by privacy features, so read every field as a best guess rather than proof. Nothing is uploaded; parsing happens in your tab.
Common questions
Where does the prefilled string come from?
From navigator.userAgent — the User-Agent your own browser reports. Clear it and paste a different string to decode someone else's, or use Detect mine to restore your own.
How accurate is the detection?
It is a heuristic. User-Agent strings follow loose, historical conventions, so the parser matches the common patterns for mainstream browsers and systems. Unusual, very old, or deliberately crafted strings may parse partially or not at all.
Can a User-Agent be faked?
Yes. Any client can send any string, extensions and dev tools can override it, and modern browsers increasingly freeze or reduce it for privacy. Never treat a parsed User-Agent as a trustworthy identity or security signal.
Why does Chrome's string also mention Safari and AppleWebKit?
For historical compatibility. Chrome and Edge are built on Blink (a WebKit fork) and still include Safari and AppleWebKit tokens, so the parser checks for the more specific brands first and reports Safari only when nothing more specific matches.
Is my User-Agent sent anywhere?
No. The string stays in your browser tab and is parsed by local JavaScript. Nothing is uploaded to a server.