The user agent string is a browser's self-description — but reading it is like deciphering ancient hieroglyphs. 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36...' carries useful information buried under layers of legacy compatibility tokens.
What Is User Agent Parser?
User agent parsing extracts structured data — browser name/version, OS, device type, and bot status — from the raw user agent string. Our User Agent Parser breaks down any UA string into readable, actionable components.
How to Use User Agent Parser on DevToolHub
- Open the User Agent Parser tool on DevToolHub — no signup required.
- Paste or enter your input data in the left panel.
- See the result instantly in the output panel.
- Copy the result or download it as a file.
Parsing a Real User Agent
Extract meaningful data from a typical UA string:
// Raw User Agent
"Mozilla/5.0 (iPhone; CPU iPhone OS 17_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.0 Mobile/15E148 Safari/604.1"
// Parsed Result
Browser: Safari 17.0
Engine: WebKit 605.1.15
OS: iOS 17.0
Device: iPhone (Mobile)
Bot: No
// Googlebot example
"Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)"
→ Bot: Googlebot 2.1Pro Tips
- Don't rely on user agents for security decisions — they're easily spoofed
- Use feature detection (Modernizr, @supports) instead of UA sniffing for browser capabilities
- Common bots: Googlebot, Bingbot, Slurp, DuckDuckBot, facebookexternalhit
- The 'Mozilla/5.0' prefix exists in nearly every browser for historical compatibility reasons
When You Need This
- Building analytics dashboards that track browser and device usage
- Detecting bots and crawlers for rate limiting or content serving
- Customizing content delivery based on device type (mobile vs desktop)
- Debugging browser-specific rendering issues by identifying exact versions
Free Tools Mentioned in This Article