A user agent parser that explains what the string really says
Every browser, app and crawler sends a User-Agent header with each request — a single line such as Mozilla/5.0 (Windows NT 10.0; Win64; x64) … Chrome/129.0.0.0 Safari/537.36. This user agent parser decodes that line into plain facts: the browser and its version, the rendering engine, the operating system, the type of device, its maker and model where available, and whether the visitor is a bot.
Open the page and it shows your own user agent straight away. If your browser supports User-Agent Client Hints, it also reads the extra details modern Chromium browsers share only on request — the real Windows version, the full browser version and the phone model — and explains where the classic string has become unreliable. Paste user agents from server logs, analytics exports or bug reports to identify them in seconds.
How to use the User Agent Parser
- Open the tool — your own browser’s user agent is loaded and parsed automatically.
- To check another one, paste it into the “User-agent string” box, or pick a sample from “Try an example…”.
- Read the summary and the details: browser, version, engine, OS, device type, vendor, model, CPU and bot status.
- Check the notes below the table — they point out frozen versions, reduced user agents and spoofable bots.
- Press “Copy as JSON” to paste the parsed result into a ticket or test case, or “Use my user agent” to return to your own.
User Agent Parser features
Wide browser coverage
Chrome, Edge, Firefox, Safari, Opera, Samsung Internet, UC Browser, Yandex, Vivaldi, in-app browsers, WebViews and legacy Internet Explorer.
Bot and crawler detection
Recognises Googlebot, Bingbot, Applebot, AI crawlers such as GPTBot and ClaudeBot, social link previewers, SEO crawlers, monitoring tools and HTTP libraries like curl.
Client Hints for your device
Uses navigator.userAgentData.getHighEntropyValues() where supported to reveal what the reduced string hides.
Device details
Separates phones, tablets, desktops, smart TVs, consoles and wearables, and maps Android model codes to makers such as Samsung, Xiaomi or Google.
Honest caveats
Flags the Windows 10/11 ambiguity, frozen macOS and iOS versions, Chrome’s “Android 10; K” placeholder and look-alike Chromium browsers.
Anatomy of a user-agent string
Most strings begin with Mozilla/5.0, a compatibility token kept for historical reasons — it says nothing about Firefox. The first bracket holds the platform: Windows NT 10.0; Win64; x64, iPhone; CPU iPhone OS 18_0 like Mac OS X or Linux; Android 14; SM-S928B. Then come the engine (AppleWebKit/537.36, Gecko/20100101) and the product tokens. Because browsers copy each other’s tokens to avoid being blocked, Edge also says Chrome and Safari, and Chrome also says Safari, so a parser must check the most specific token first.
User-agent reduction and Client Hints
To reduce fingerprinting, Chromium-based browsers now freeze most of the string: the version is sent as 129.0.0.0, Android devices claim to be “Android 10; K”, and desktop platforms report fixed values. Safari and Firefox have long frozen the macOS version at 10.15. The detail has moved to User-Agent Client Hints: a script calls navigator.userAgentData.getHighEntropyValues(), or a server sends an Accept-CH header and receives Sec-CH-UA-* request headers. Client Hints are currently available in Chromium browsers such as Chrome, Edge, Opera and Samsung Internet, but not in Firefox or Safari.
In practice, use the user agent for broad analytics and for spotting bots, and use feature detection in JavaScript — not browser sniffing — to decide what code to run. To see more about your own setup, try My Browser Info and the screen resolution checker.
Identifying bots safely
- A user agent is just text — scrapers often pretend to be Googlebot. Confirm real search crawlers with a reverse DNS lookup of the IP (it should end in googlebot.com, google.com or search.msn.com) followed by a forward lookup that returns the same IP.
- Well-behaved crawlers, including AI crawlers like GPTBot, follow robots.txt. Control them with the robots.txt generator.
- Link previewers (WhatsApp, Slack, Facebook) fetch a page once to build a card; they are not real visitors.
- Headless Chrome and HTTP libraries usually mean automation or testing, which may be legitimate — such as your own monitoring.
User Agent Parser FAQ
What is my user agent?
It is the string shown in the box when you open this page — your browser sends it with every request. The user agent parser decodes it into browser, operating system and device, and adds Client Hints when your browser supports them.
Why does my Windows 11 PC show as Windows 10?
Windows 11 browsers still send “Windows NT 10.0”. Only Client Hints can tell them apart: Chromium browsers report a platformVersion of 13.0.0 or higher on Windows 11. If your browser supports them, this tool uses them automatically for your own device.
Why does every Android phone show “Android 10; K”?
Chrome’s user-agent reduction replaces the real Android version and model with fixed values to make users harder to fingerprint. Websites that need the model can request it through Client Hints.
Can I detect Brave from the user agent?
No. Brave deliberately sends the same user agent as Chrome. Its own navigator.brave API can identify it from JavaScript, which this tool checks for your own browser, but a pasted string cannot reveal it.
How accurate is user-agent parsing?
It is reliable for the browser family and operating system, and for well-known bots. Exact OS versions, device models and genuine bots versus impostors cannot be guaranteed, because the string can be frozen, reduced or faked by any client.
Is the user agent I paste sent anywhere?
No. Parsing is done by JavaScript in your browser. Nothing you paste is uploaded or stored.