What is my user agent?

The string is read twice: from the HTTP header our server received and from navigator.userAgent in your browser. They are normally identical; a difference means a proxy, an extension or a privacy setting is rewriting one of them.

Chrome, Firefox, Safari, Edge, Samsung Internet, Opera and others identify themselves by name and version. Since 2023 Chromium browsers send a reduced user agent: the major version is real, the minor version is always 0.0.0. The exact version is available only through Client Hints (below).

Windows, macOS, Linux, Android, iOS or ChromeOS. The version is frozen in reduced user agents — Windows shows 10.0 on Windows 11, macOS shows 10_15_7 on every current release — so the string cannot tell them apart; Client Hints can.

Desktop, phone or tablet, inferred from tokens such as Mobile and Android, and the model name on Android (also frozen to K in reduced user agents). iPads report themselves as Macs in Safari's desktop mode.

Blink (Chrome, Edge, Opera, Brave, Samsung), Gecko (Firefox) or WebKit (Safari, and every browser on iOS, where Apple requires WebKit). This is what actually decides how a page renders.

If you only want to know which browser you are using and whether it is up to date, the decoded card gives the name and major version; compare it with the latest release on the vendor's site. An outdated major version is the most common reason a site "does not work" — and a security risk. The what websites can see about you page shows the user agent in the context of everything else a site learns.

Paste a user agent from a log file, an analytics report or a support ticket and press Parse. The parser runs in your browser and handles the main desktop and mobile browsers, in-app browsers (Facebook, Instagram, WeChat), search-engine crawlers and common bots. Unknown strings are shown with the tokens we could identify.

User-Agent Client Hints are the structured replacement for the user agent string in Chromium browsers. By default a site receives only the browser brands with major versions, the platform and whether the device is mobile; it can request more (full version, platform version, architecture, model) with the Accept-CH header, and the browser decides whether to grant it. We show the low-entropy hints your browser sends automatically and, where supported, the high-entropy values it allows us to read, so you can see what a site can learn beyond the string. Firefox and Safari do not implement Client Hints.

Changing the user agent makes sites treat you as a different browser — useful for testing, for forcing a desktop layout on a phone, or for working around a badly written compatibility check. It does not make you anonymous; the rest of your fingerprint stays the same.

Open DevTools (F12) › the three-dot menu › More tools › Network conditions › untick Use browser default and pick or type a user agent. It applies while DevTools is open. For a permanent change, use an extension such as a user-agent switcher.

Type about:config, create a string preference named general.useragent.override and set it to the string you want. Delete the preference to restore the default. Extensions offer per-site switching.

Enable the Develop menu (Settings › Advanced › Show features for web developers), then Develop › User Agent › pick a preset or Other…. The change applies to the current tab until you close it.