Whenever you visit a website your browser hands over a user agent, a text string which tells the site about your browser, operating system, plugins and more.

This scheme was designed to help sites customise themselves to different devices, but user agents can be misused to help fingerprint your computer and track you online.

Random User-Agent is a free Chrome extension which combats this by giving you a new and random user agent at regular intervals, or on demand.

Install the add-on and it kicks in immediately. If you’re curious, clicking the address bar icon displays your shiny new browser ID.

By default the user agent is updated every ten minutes, but this is adjustable in Settings, or you can tap “Get New Agent” to replace the user agent immediately.

Get a random user agent automatically, or on demand in a couple of clicks

One issue with this kind of tool is you’re intentionally providing websites with inaccurate information about your system. As a result, it’s possible they might try and serve you a web page which doesn’t work properly on your computer.

Random User-Agent tries to reduce problems by making minimal changes only. By default its randomised agents always specify that you’re using Chrome, only changing version numbers and operating system.

If this doesn’t suit your needs then you can minimise the agent switching even further – just Chrome on Windows, say – or you can expand it to cover IE, Firefox, Safari, Opera and more.

An “Exceptions” box acts as a whitelist, disabling Random User-Agent when you’re at a matching site. Wildcards are supported, so entering *google.* will match www.google.com, news.google.com, www.google.co.uk, mail.google.com and so on.

None of this guarantees your safety. User agents are a very basic form of tracking, and determined sites now have many other browser APIs they can use for fingerprinting. User agent switching still offers some protection, though, and Random User-Agent is so configurable that it keeps any browsing hassles to a minimum.

Random User-Agent is a free extension for Google Chrome.