User Agent Parser
Decode a browser user-agent string into its browser, version, rendering engine, operating system and device type. Parses in your browser.
Browser
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How it works
The parser scans the user-agent string for the tokens browsers use to identify themselves, checking the more specific ones first, Edge and Opera both carry a Chrome token, so they are matched before Chrome, and Chrome before Safari.
User-agent strings are deliberately messy for backward compatibility and can be spoofed, so treat the result as a best-effort guess rather than proof. Nothing is sent anywhere, the string is parsed entirely in your browser.
What this does
A user-agent parser decodes a browser user-agent string into its browser, version, rendering engine, operating system and device type.
How to use it
- Paste a user-agent string.
- Read the browser and version.
- See the engine, OS and device.
How it works
For compatibility, user agents pile on legacy tokens — most include “Mozilla” and “like Gecko”. The parser checks the more specific tokens first. A user agent can be spoofed, so treat it as a best guess.
Understanding your result
The decode is a best guess, not proof: user-agent strings are easy to spoof and pile on legacy tokens like Mozilla and like Gecko for compatibility, so never use them for security decisions. They are fine for rough analytics and serving compatible content, but treat the detected browser, OS, and device as advisory rather than authoritative.
Example
A Chrome string reports Chrome, its version, the Blink engine and the operating system.
Sources & methodology
Last updated .
Frequently asked questions
What is a user-agent string?
It is a line of text your browser sends with every request to identify itself, the browser and version, the rendering engine, and the operating system and device. Servers use it to tailor responses.
Why are user agents so messy?
For backward compatibility, browsers pile on tokens from older ones, most still include "Mozilla" and "like Gecko", and Chromium-based browsers carry a Chrome token. The parser checks the more specific tokens first to tell them apart.
Can a user agent be trusted?
Not entirely. It is set by the client and can be changed or spoofed, so treat the result as a best-effort guess rather than proof of the real browser or device.
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