User Agent Parser
Parse a User-Agent string into browser, rendering engine, operating system and device type. Prefilled with your own UA — free, instant and private in the browser.
What is the User Agent Parser?
The ByteTools User Agent Parser breaks down any User-Agent string into the four things you usually want to know: the browser and its version, the rendering engine, the operating system, and whether the client is a desktop, tablet or mobile device.
- Detects browser and version across major vendors
- Identifies the rendering engine (Blink, WebKit, Gecko, Trident)
- Recognises Windows, macOS, iOS, Android, Linux and Chrome OS
- Classifies device type: desktop, tablet or mobile
- Prefilled with your current browser's User-Agent
- 100% client-side — heuristic parsing, no external service
How to use the User Agent Parser
- 1
The tool loads with your own User-Agent string already filled in.
- 2
Paste a different User-Agent string to analyse another client.
- 3
Read the detected browser, rendering engine, operating system and device type.
- 4
Copy any value you need for your notes or bug report.
About the User Agent Parser
The ByteTools User Agent Parser breaks down any User-Agent string into the four things you usually want to know: the browser and its version, the rendering engine, the operating system, and whether the client is a desktop, tablet or mobile device.
It prefills with your current browser's User-Agent so you can see the result immediately, and you can paste any other UA string to analyse it. Parsing uses a set of heuristic regular expressions rather than an external service, recognising the major browsers, engines and operating systems.
All parsing runs locally in your browser, so nothing is uploaded. It is a fast way to understand a UA string from an analytics log, a bug report or a server header without pulling in a library or hitting an API.
Frequently asked questions
What is a User-Agent string?
A User-Agent is a text header your browser sends with every request to identify itself. It packs together the browser name and version, the rendering engine, and the operating system, which servers use to tailor responses.
How do I parse a User-Agent string?
Paste the string into the box and the tool applies pattern matching to extract the browser, engine, operating system and device type. It loads prefilled with your own User-Agent so you can see how the parsing works straight away.
Why does Chrome's User-Agent mention Safari and Mozilla?
For historical compatibility, most browsers include legacy tokens like Mozilla and, for Blink and WebKit browsers, Safari and AppleWebKit. The parser accounts for this and reports the actual browser rather than being fooled by those tokens.
Is User-Agent parsing reliable?
It is a well-informed best guess. User-Agent strings can be freely spoofed or reduced by privacy features, so treat the result as an indication rather than a guarantee, especially for security-sensitive decisions.
How can I find my own User-Agent?
This tool shows it automatically — the input is prefilled with your current browser's User-Agent string the moment the page loads, so you can read and copy it directly.
Is my User-Agent sent anywhere?
No. The parsing happens entirely in your browser using local pattern matching, so no string you enter is transmitted to any server.
Guides for User Agent Parser
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