Free tool
Browser Privacy Check
Measures the fingerprinting surfaces your browser exposes: canvas, WebGL, audio, fonts, WebRTC and more. Everything runs locally and nothing is transmitted.
Reading fingerprinting surfaces locally. Nothing leaves this page.
How fingerprinting works
Cookies require storing something on your device, which you can delete. Fingerprinting requires storing nothing. A script asks your browser a series of ordinary questions, then combines the answers into an identifier that is stable across sessions because your hardware and configuration are stable.
Individually these details are harmless. Your timezone narrows you to a few hundred million people. Your screen resolution narrows that considerably. Your exact GPU model, your installed font list and the precise way your graphics stack renders a test image narrow it much further. Combined, they are frequently enough to single out one device.
What each signal contributes
| Signal | Why it identifies you | Weight |
|---|---|---|
| Canvas | GPU, drivers and font rasterisation produce a pixel-exact image hash | High |
| WebGL renderer | Exposes your specific graphics hardware by name | High |
| Font list | Installed fonts vary enormously between machines | High |
| WebRTC | Can leak your local network address regardless of VPN | High |
| Audio stack | Device-specific floating point rounding in audio processing | Medium |
| Screen and DPR | Unusual resolutions and scaling are distinctive | Medium |
| Timezone and locale | Combined with an IP address, narrows to a small group | Medium |
| User agent | Sent with every request, though deliberately reduced in modern browsers | Low |
Why this tool refuses to give you a uniqueness number
A claim like "your browser is unique among 312,441 tested" sounds precise and is usually close to meaningless. It is calculated against whoever happened to visit that particular tool, a self-selecting group of privacy-interested users that resembles the general population very little. It also requires the tool to retain a record of every visitor's fingerprint, which is an odd thing for a privacy tool to do.
We score exposure instead: how many distinct identifying signals your browser hands over without being asked. That is directly measurable, it needs no database, and it maps cleanly onto action, because every exposed signal is one you can potentially close.
What actually reduces your exposure
Blocking the known fingerprinting vendors removes the majority of real-world commercial fingerprinting, because the practice is concentrated among a handful of companies rather than implemented independently by every site. That is what a tracker blocker does, and you can see which of those vendors load on any given site with our tracker scanner.
Browser choice matters for the rest. Some browsers randomise canvas readback per session, which makes the signal useless for linking visits. We compare the defaults in Brave versus Chrome, and the mechanics are covered in how fingerprinting and tracking cookies differ.
Frequently asked questions
What is browser fingerprinting?
It is identification by configuration rather than by cookie. A site reads dozens of small details about your browser and device, such as your graphics hardware, installed fonts, screen dimensions and timezone, and combines them into a signature. The signature persists after you clear cookies and follows you across sites.
Why does this tool not tell me how unique I am?
Because an honest answer requires a large, current database of other visitors to compare against, and we do not keep one. Tools that quote a figure like one in 300,000 are measuring against their own visitor population, which is not the population that matters. We score how many identifying signals your browser exposes instead, which is measurable without tracking anyone.
Does this tool store my fingerprint?
No. Every check runs in your browser and no result is transmitted. There is no network request in the measurement code at all. You can confirm this by opening your browser developer tools and watching the network tab while the test runs.
Can an ad blocker stop fingerprinting?
Partly. Blocking the known fingerprinting scripts prevents most commercial fingerprinting, because the majority of it is performed by a small number of vendors. It cannot stop a site that implements fingerprinting itself in first-party code, which is why browser-level protections like canvas randomisation matter alongside blocking.
What is the single most effective change I can make?
Use a browser that randomises or blocks canvas and WebGL readback, since those two signals carry the most identifying information. Beyond that, blocking the commercial fingerprinting vendors removes most real-world tracking, and avoiding browser extensions that alter page rendering reduces how distinctive your setup looks.