Dev Tools
User-Agent Parser
Decode a User-Agent string from a support ticket or server log into browser, OS, and device type.
Matched against common browser and OS patterns, not a full device database. Unusual or spoofed strings may not match cleanly.
Related: the email header analyzer for parsing other raw text blocks.
Runs entirely in your browser. Nothing you paste is sent anywhere.
Learn about User-Agent strings
Why they look so messy
Browsers have copied each other's naming for decades for compatibility reasons, so a modern Chrome User-Agent string still contains the word "Mozilla," and often "like Gecko" and "Safari," despite being none of those things. It reads less like a clean self-description and more like a fossil record of browser history.
Reading your results
This tool extracts a browser, OS, and device type by matching the string against known patterns, since there's no strict standard format to parse directly. That also makes the process inherently a bit probabilistic. A brand-new browser version or an unusual User-Agent can be misidentified until pattern lists catch up with it.
Common questions
Why does a User-Agent string seem to claim to be several browsers at once? That's the compatibility layering mentioned above. Each browser added references to older ones so that sites checking for those older strings wouldn't break.
Can a User-Agent string be trusted? Not fully. Any client can send an arbitrary User-Agent string, so it's genuinely useful for analytics and general compatibility decisions, but it shouldn't be relied on for anything security-sensitive, like restricting access based on a claimed browser or device.
Why does "Mobile" show up in a User-Agent on a tablet, or not show up on a phone? Device classification inside the string is inconsistent across vendors and has shifted over time for compatibility reasons, so it's a rough signal rather than a precise device classification.