The browser User-Agent string is displayed and parsed into useful browser, platform and device-family information where it can be identified reliably.
Browser tool
User agent checker
See the identification string your browser sends with requests.
BrowserUnknown browser
PlatformUnknown platform
Raw user agent
Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
Quick guide
What is a user agent?
A user-agent string is sent by many browsers and clients to identify the software making a request. Sites can use it for compatibility decisions, diagnostics and analytics.
Modern browsers often reduce or standardise parts of the user-agent string, so it should not be treated as a perfect hardware or identity fingerprint.
- Checking what User-Agent a browser sends
- Debugging UA-based behaviour
- Comparing browser and device strings