AmIUnique, explained
AmIUnique tells you whether your browser fingerprint is unique among the millions it has collected. Almost every browser is, including an ordinary one used by a person, so the useful part is the per-attribute table underneath.
An academic research project on browser fingerprinting. Open AmIUnique
What is AmIUnique?
AmIUnique (amiunique.org) is a research project that has been collecting browser fingerprints for over a decade to study how identifying they are. After the test it tells you whether your fingerprint is unique in its dataset, which held about 5.5 million fingerprints in September 2026.
Below the headline is a table of attributes, from the user agent to canvas and fonts, each with a similarity ratio: the share of fingerprints in the dataset that have the same value. You can also compare yourself against the last 7, 15, 30 or 90 days instead of all time.
What AmIUnique checks
HTTP headers
User agent, Accept, content encoding and language as your browser sends them.
JavaScript attributes
User agent, platform, time zone, languages, screen, cores, memory and more, as read by scripts.
Rendering
Canvas and WebGL output, and the list of fonts.
How to read your AmIUnique result
- "Yes! You are unique"
- No other fingerprint in the dataset matches yours exactly. That is the usual result, not a warning.
- Similarity ratio
- The share of fingerprints with the same value. A very low ratio marks the attribute that makes you stand out.
- Time window
- Switch to the last 30 or 90 days for a comparison with current browsers instead of ten years of history.
What real browsers scored
Measured on 20 and 21 September 2026 on one Windows 11 PC (NVIDIA RTX 3070) on a home fibre connection in the Netherlands, with no proxy or VPN. Three browsers: a person's everyday Chrome 153 with an ad blocker, used by hand; the same genuine Chrome 153 driven by Playwright; and Clearcote 153 driven by Playwright with a fingerprint seed.
| Browser | AmIUnique said |
|---|---|
| Everyday Chrome 153, by hand | Unique among 5,531,402 · user agent 0.06% · canvas 0.04% |
| Genuine Chrome 153, Playwright | Unique among 5,528,534 · user agent 0.05% |
| Clearcote 153, Playwright + seed | Unique among 5,528,528 |
All three were unique, including the person's own Chrome. Part of the reason is simply being up to date: Chrome 153 had been out for under two weeks, so only about 0.06% of the dataset shared its user agent.
Results that show up on normal browsers
- "You are unique" on a completely ordinary browser. It is the normal result.
- A tiny similarity ratio for the user agent right after a Chrome update. The dataset hasn't caught up with the new version yet.
FAQ
Is it bad to be unique on AmIUnique?
Not in itself. Almost every browser is unique in a dataset this detailed, including a normal one used by a person. What matters for tracking is whether your fingerprint stays the same over time and across sites.
Who runs AmIUnique?
It is an academic research project on browser fingerprinting. The data it collects is used to study how identifying fingerprints are.
How do I stop being unique?
You generally can't make a browser non-unique. Privacy-focused browsers instead make the fingerprint change between sites or sessions so it can't be used to link your visits.
Does being unique mean a site can tell I'm a bot?
No. Uniqueness is about tracking. Bot detection looks for different things, such as automation flags and values that contradict each other.
Want every check explained?
The Clearcote audit runs 272 coherence checks on whatever browser opens it, with a plain-English explanation and a fix for each one. Free, no account.
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