Browser fingerprinting, and what Brave Shields do

Websites can recognise your browser without a cookie and without you logging in. They read dozens of small details about it and combine them into a fingerprint that is close to unique. That fingerprint follows you from one site to the next, and clearing your cookies or opening a private window does not remove it.

What gets measured

A fingerprint is built from many small signals: your screen size, your timezone and language, the fonts you have installed, and the exact way your browser draws graphics and plays sound. Any one of those is common. Put enough of them together and they point at you and almost no one else.

What Brave Shields do

Brave Shields is the protection built into the Brave browser, switched on by default. It does two jobs. It blocks third-party trackers and ads outright. And it adds a small amount of random noise to the signals a fingerprint is built from, such as the graphics and audio readings, different for every site and every session. Your fingerprint then looks different each time, so it cannot be used to join up your visits. This is the opposite of Tor Browser, which tries to make every user look identical.

Settings worth changing

• Set Shields fingerprinting protection to Strict.
• Keep third-party cookies blocked, which is the default.
• Set WebRTC so it cannot leak your real address when you are on a VPN.

What it does not fix

Signing in tells the site exactly who you are, so none of this helps once you log in. Keep anything sensitive to a separate browser profile that you never sign into. A few plain details, like your browser version, still get through.

When you want more

For the strongest resistance, Mullvad Browser uses the same hardening as Tor Browser, where everyone looks the same, but runs over your normal connection or a VPN instead of the Tor network. It is a good choice for sensitive research on a computer. Tor Browser adds network anonymity on top of that, and is slower for it.