Browser fingerprinting identifies a browser by the details it gives away, rather than by storing something on it. Cookies can be cleared or blocked. A fingerprint is recalculated from scratch on every visit, so clearing cookies or opening a private window often leaves it unchanged.
How it differs from cookies and your IP address
A cookie is an ID a site stores on your device. Your IP address belongs to your network and changes when you switch Wi-Fi or use a VPN. A fingerprint belongs to the browser and device itself. A VPN does not change it, and it follows you across networks. That is why ad-tech and anti-fraud systems combine all three.
Which signals matter most
- Canvas and WebGL carry the most detail, because they expose how your exact GPU, driver and OS draw graphics.
- Installed fonts reveal software you have installed, such as Microsoft Office, Adobe apps or language packs.
- Language list and time zone are low-detail alone but powerful in combination with everything else.
- Request headers reach every server you contact, before any script runs, so blocking JavaScript does not hide them.
Why your ID might change
Any change to one signal changes the whole ID. Browser and OS updates, a new GPU driver, a newly installed font, an external monitor or a different language setting can all do it. Real trackers match fingerprints approximately, so a small change does not always make you a stranger.
How to reduce your fingerprint
Hiding individual values rarely helps. A rare setting can make you more distinctive. What works is a browser that either makes everyone look the same or randomises the noisy signals:
- Tor Browser makes users look identical: the same window size, fonts, time zone and user agent.
- Brave randomises canvas, WebGL and audio output for each site and session.
- Firefox with
privacy.resistFingerprintingblocks or normalises many signals. - Safari with Advanced Tracking and Fingerprinting Protection adds noise to canvas and audio and limits fonts to system ones.
If this page shows a randomised or blocked badge, your browser is doing exactly this. Signals marked that way are left out of the fingerprint ID.
What this test does not do
It does not tell you how rare your fingerprint is. That would need a database of other visitors, and this tool deliberately keeps none. It shows what your fingerprint is made of, not how many people share it.