Web

User-Agent Parser

Extract likely browser, engine, OS, and device information from a User-Agent string for log inspection.

Local processing

Loading tool workspace...

About this tool

When to use it

Extract likely browser, engine, OS, and device information from a User-Agent string for log inspection.

How to use it

Use the current browser string or paste a captured test string, then select Parse User-Agent. Treat Unknown values as missing evidence and combine the result with feature detection when debugging behavior.

Guide updated 2026-09-15. Examples checked against this implementation.

Worked examples

A desktop Chrome fixture

Input

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Expected output

browser: Chrome; os: Windows; cpu: amd64

The string is a test fixture, not a statement about the current browser. These are inferred labels from the parser's rules.

Errors and unsupported input

Device type is Desktop or unknown

The string may omit a device category. Do not turn that fallback into a verified desktop classification.

Continue this workflow

Device Information: Compare the parsed string with browser-exposed environment information.

Format rules and limitations

Input is limited to 256 KiB. Browser privacy reduction, spoofing, and parser metadata affect results.

The tool does not identify a user, prove hardware ownership, or test whether an API is supported.

Privacy and security

The workspace processes data locally in your browser. Copy writes to the system clipboard; downloads persist on your device. Share, where offered, sends the selected result to your chosen app or copies it to the clipboard. The page also loads site assets and may contact configured analytics or consent services; tool input and output are not included in DevMate analytics. Review a report before sharing it, especially when it contains credentials or device details.

Review sensitive or production-critical output in the trusted system where it will be used.

Questions

Frequently asked questions

Can I trust the parsed version for access control?

No. The input is a client-supplied claim. Security and feature decisions need trusted checks appropriate to the application.