How identifiable is your browser?
Even without cookies, the small facts your browser shares can add up to a near-unique signature. This test gathers those signals and estimates how much you stand out. Everything runs on your device.
What browser fingerprinting is
Fingerprinting is a way to recognise a browser from the combination of its characteristics rather than from a stored identifier like a cookie. Any single characteristic, say that you use a common browser on a common operating system, is shared by millions of people. But stack enough of them together (your exact screen size, your timezone, your language list, your graphics hardware, tiny quirks in how your device draws text on a canvas) and the odds that anyone else matches you exactly drop fast.
The unsettling part is that it needs no permission and no storage. A script reads these values as a page loads, hashes them, and can recognise you again later even if you clear cookies or switch to private browsing. That is why fingerprinting is a favourite of trackers and, more defensibly, of anti-fraud systems that want to spot a returning device.
How to read your score
The entropy figure is measured in bits. Each bit roughly doubles the number of distinct browsers a value can distinguish, so more bits means you are more identifiable. A result in the low range means you blend in with a large crowd; a high range means your particular combination is rare. The WebGL renderer and canvas signals usually dominate, because your graphics hardware and its driver are far less common than your browser name.
How to become less unique
- Use a browser with built-in anti-fingerprinting. Tor Browser makes users look identical to one another, and Brave and Firefox add protections that mask or randomise the strongest signals.
- Keep a mainstream, up-to-date setup. A current, common browser version on a common OS means your signals match the crowd. Ironically, heavy customisation makes you easier to fingerprint, not harder.
- Go easy on rare extensions and fonts. Unusual installed fonts and some extensions add distinctive signals.
- Understand each signal. The WebGL renderer, user agent, screen resolution and timezone pages explain what each one reveals and how to soften it.