User-Agent Parser — Decode Browser, OS & Device from a UA String (free)
Decode any User-Agent string into browser, OS, device, engine and CPU details — prefilled with your own UA, with copy-as-JSON. Free, in your browser.
| Field | Value |
|---|---|
| Browser | — |
| Browser version | — |
| Engine | — |
| Engine version | — |
| Operating system | — |
| OS version | — |
| Device type | — |
| Device vendor | — |
| Device model | — |
| CPU architecture | — |
🔒 Parsed in your browser — nothing is uploaded.
Free User-Agent parser — nothing uploaded
A User-Agent (UA) parser decodes the User-Agent string a browser or app sends with every HTTP request into the pieces you actually care about: which browser and version, which rendering engine, which operating system, the device type and model, and the CPU architecture. Paste any UA string — or use the one your own browser is sending, which is prefilled for you — and the parsed details appear instantly in a table. Everything runs in your browser, so there is no account and nothing is sent to a server.
What each field means
- Browser & version — the client software, e.g.
Chrome 120,Mobile Safari 17,Firefox. - Engine & version — the rendering engine behind it, e.g.
Blink,WebKit,Gecko. - Operating system & version — e.g.
Windows 10,iOS 17,Android 14,macOS. - Device type, vendor & model —
mobile,tablet,console,smarttvor blank for a desktop; plus vendor and model when the UA reveals them (e.g.Apple iPhone). - CPU architecture — e.g.
amd64,arm64, when present.
How to find and read your own User-Agent
Your browser's current User-Agent is prefilled in the box, so you can see exactly what websites and servers receive from you. Click Use my browser to reload it, edit the field to test any other UA string, or paste one from a server log to identify the client. The parsed result updates as you type, and Copy JSON gives you a structured object you can drop straight into code or a bug report.
Why User-Agent detection is a best-effort guess
User-Agent strings are self-reported and freely spoofable, and modern browsers deliberately freeze or reduce them (Chrome's UA reduction, plus User-Agent Client Hints) to limit fingerprinting. That means a UA can be missing details, mimic another browser, or report an old version on purpose. Treat the parsed output as a strong hint rather than proof — for feature support, prefer capability detection over UA sniffing.
Great for debugging logs and support tickets
When a bug only reproduces on one browser or device, the User-Agent from a server log or error report is often the fastest clue. Paste it here to turn an opaque one-liner into a readable browser/OS/device breakdown, then copy the JSON into your issue tracker.
Private by design
Parsing happens entirely in your browser with JavaScript — the User-Agent string you paste never leaves your device. That is why there is no sign-up.
Frequently asked questions
What is a User-Agent string?
It is a line of text a browser or app sends in the User-Agent HTTP header with every request, such as 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36'. Servers read it to guess the browser, OS and device — this tool decodes it into readable fields.
What does this User-Agent parser detect?
Browser and version, rendering engine and version, operating system and version, device type/vendor/model, and CPU architecture. Fields the string doesn't reveal are shown as a dash rather than guessed.
How do I find my own User-Agent?
It's already prefilled — the box shows the User-Agent your browser is sending right now. Click 'Use my browser' to reload it, or paste any other UA string to parse it instead.
Why is my device or browser detected incorrectly?
User-Agent strings are self-reported and easily spoofed, and modern browsers intentionally freeze or trim them to reduce fingerprinting. A UA can therefore be incomplete, impersonate another browser, or omit the device model. Treat the result as a strong hint, not proof.
Should I use User-Agent sniffing for feature support?
Generally no. Because UA strings are unreliable and frozen, the web-standard advice is to use feature/capability detection instead. This parser is best for identifying clients in logs, analytics and bug reports — not for deciding which code path a browser can run.
Is my User-Agent uploaded anywhere?
No. The string is parsed entirely in your browser with JavaScript and never sent to any server. That is why there is no sign-up.