What is my user agent?
Your browser's User-Agent string and Client Hints, exactly as our server received them and as scripts read them, and whether they all tell the same story.
Reading your browser…
The current Chrome user agents (Chrome 154)
Every Chrome 154 sends one of these, whatever the exact build, OS version or device: the rest is frozen. The Chrome user agent page has every platform, the Client Hints that go with them and a generator for other versions.
| Windows | Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.36 |
|---|---|
| macOS | Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.36 |
| Linux | Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Safari/537.36 |
| Android (phone) | Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/154.0.0.0 Mobile Safari/537.36 |
With it, on every request: Sec-CH-UA: "Chromium";v="154", "Google Chrome";v="154", "Not A(Brand";v="99".
How this page reads your user agent
Three places, compared with each other. The request: our server reports back the User-Agent and Sec-CH-UA headers your browser sent it, because page scripts cannot read those; the page asks for the detailed Client Hints with an Accept-CH header, so they are included too. The page: navigator.userAgent, navigator.userAgentData and its high-entropy values. A worker: the same values read in a background thread, which overrides applied to the page often miss.
A real browser derives all of them from one version and one platform, so they agree. Each check above compares two of them and fails only on a contradiction; none of them looks your browser up in a list. The browser fingerprint test runs the same idea across a few hundred signals.
FAQ
What is a user agent?
A short text a browser sends with every request, in the User-Agent header, and exposes to scripts as navigator.userAgent. It names the browser, its version and the operating system, so a site can adapt what it serves. It is also one of the first things bot detection reads.
Why does my user agent say Chrome/154.0.0.0 instead of my exact version?
Chrome reduced its User-Agent string: only the major version is real, and the minor, build and patch numbers are always zero. The full version is still available, but only as a Client Hint (Sec-CH-UA-Full-Version-List) that a site has to ask for.
Why does it say Windows NT 10.0 on Windows 11?
Chrome freezes the operating system part of the string: every Windows version reports Windows NT 10.0; Win64; x64, every Mac reports Intel Mac OS X 10_15_7 (Apple silicon too), and every Android phone Android 10; K. The real OS version is in the Sec-CH-UA-Platform-Version Client Hint; on Windows 11 it is 13.0.0 or higher.
What are User-Agent Client Hints?
Headers that carry what the User-Agent string used to: Sec-CH-UA (the brands and major version), Sec-CH-UA-Mobile and Sec-CH-UA-Platform go with every request; the detailed ones (full version, OS version, CPU architecture, device model) only when a site asks with an Accept-CH header. Scripts read the same values through navigator.userAgentData. Chromium browsers send them; Firefox and Safari do not.
What is "Not A(Brand" in my Sec-CH-UA header?
A deliberately fake brand, called GREASE, that Chrome adds so that servers do not hard-code the exact list. Its name, its version (8, 24 or 99) and the order of the whole list are computed from the major version, so every Chrome of one version sends the same list, and the next version a different one. The Chrome user agent page lists them per version and links the Chromium source.
Can websites see my real user agent if I change it?
Usually, yes. A user-agent switcher or an automation setting typically changes the User-Agent header and navigator.userAgent, but not the Client Hints, not the value inside a worker, not navigator.platform, and not the dozens of engine features that differ between versions. The checks above compare exactly those, and a site can do the same.
Is anything stored?
No. The page asks our server to report the headers it received and returns them to you; nothing is written anywhere. Everything else runs in your browser.
Related free tools
Chrome user agent strings
The latest Chrome user agents and Sec-CH-UA headers, and a generator for any version.
Random user agent generator
Current Chrome, Edge and Firefox user agents, each with its Client Hints.
What browser am I using?
Your browser and version, and whether it is up to date.
JA4 fingerprint checker
Your TLS and HTTP/2 fingerprints next to Chrome's and common HTTP clients'.
Clearcote puts this into practice
An open-source Chromium with fingerprint control compiled into the engine. A drop-in for Playwright & Puppeteer.
Free for one browser with GitHub. No card.