HTTP

User-Agent Parser

Parse User-Agent string. Detect browser, OS, device, bot. 100% client-side.

UA sniffing is unreliable; prefer feature detection when possible.

How to use

  1. Enter a domain, URL, or value relevant to User-Agent Parser.
  2. Run the check and review the output carefully.
  3. Apply recommended fixes, then run the check again to verify.

Common use cases

  • Pre-deployment validation for User-Agent Parser.
  • Incident triage when security checks fail in production.
  • Periodic security review as part of technical SEO and hardening.

Example inputs

Mozilla/5.0 (Windows NT 10.0; Win64; x64) Chrome/120.0.0.0

Common issues and fixes

Empty or unknown UA

Some clients send minimal UA. Detection may show Unknown for rare browsers.

Spoofed User-Agent

UA can be faked. Do not use for security decisions. Use for analytics only.

Bot vs browser confusion

New bots may not be detected. Check for crawler keywords in raw string.

Recommended remediation

Use navigator.userAgent to get current UA. For server-side, read User-Agent header. Don't rely on UA for auth.

FAQ

Is User-Agent Parser free to use?

Yes. This tool is free and can be used without account registration.

Do you store submitted values?

Only the minimum processing needed for the check. For client-side tools, data stays in your browser.

How should I use these results?

Use the output as a diagnostic baseline, apply fixes in your stack, then re-run the check to confirm remediation.

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