UtilibyWritten by the Utiliby editorial team · Last updated October 14, 2026 · Rules and formulas reviewed October 2026
What this free browser fingerprint checker does
You can delete cookies, browse in a private window and use a VPN, and a website may still recognize your browser. It does so by asking the browser a long list of harmless-looking questions: which fonts are installed, how big is the screen, which graphics card draws the page, which language and time zone are set. Each answer is common on its own, but together they can be nearly unique. This is browser fingerprinting.
This free online browser fingerprint checker shows you exactly what any site can read from your browser, with the value, a reveal level and a plain-English reason why it matters. It builds a short browser ID so you can see how the details combine, tests whether your browser is adding noise to resist tracking, and gives practical steps to reduce what you leak. All checks run in your browser and nothing is uploaded.
How to use the fingerprint checker
- Open the page. The checks run at once.
- Read the summary. The bar and the label show how distinctive your details are, and the browser ID shows the combined result.
- Study the table. High items are the strongest identifiers. Each row explains why it matters.
- Check the protection signals. They show whether your browser appears to resist fingerprinting.
- Change something and check again. Switch browsers or settings, then press the button to see the effect.
What is measured and why
| Signal | Why it identifies you |
|---|---|
| User agent and platform | Browser, version and operating system |
| Screen, window and pixel ratio | Many devices share values, but few share all three |
| Fonts | Installed fonts vary by system and by user |
| Canvas | Drawing output depends on fonts and graphics drivers |
| WebGL | Graphics card and driver details |
| Audio | Audio processing differs by hardware and browser |
| Language and time zone | Narrow you to a region or community |
| CPU threads and memory | Hardware class |
The more common your value, the less it reveals. A very popular phone model on the default settings blends in. A desktop with rare fonts and a wide screen stands out.
How the identifying bits are estimated
The score adds up approximate bits for each signal. A bit halves the group that shares your value, so 10 bits mean about one in a thousand and 20 bits about one in a million. The per-signal values are rough averages taken from published fingerprinting studies, and they are not measured against real visitors, so treat the total as a guide to which details matter most and not as an exact probability. Details that depend on each other, such as the user agent and platform, are not fully independent, so the real total is usually lower than the sum.
How to reduce your fingerprint
- Use a browser designed for it. Tor Browser makes all users look the same. Brave adds noise to canvas, audio and WebGL. Firefox has a resist fingerprinting setting.
- Keep it standard. Avoid rare fonts, a custom window size and extra extensions.
- Limit what pages can run. Blocking third-party scripts removes many trackers.
- Update your browser. Newer versions add protection.
- Do not mix ideas. Changing one value only, such as the user agent, usually makes you more unique.
What a VPN, private mode and cookies do and do not do
A VPN changes your IP address, not your browser details. Private mode deletes cookies and history at the end of a session, but the browser reports the same fingerprint during it. Clearing cookies helps against cookie tracking, and fingerprinting is designed to work when cookies are gone. Strong protection combines a privacy-focused browser, tracker blocking and sensible habits. No setup gives perfect anonymity.
How fingerprints are used
Advertisers use fingerprints to link visits across sites and to rebuild a profile after cookies are cleared. Banks and shops use them to detect fraud, such as a login from a new device. Anti-bot services use them to tell people from scripts. The same technique is therefore both a privacy risk and a security tool, and many laws now treat it as tracking that requires notice or consent.
Fingerprints, cookies and IP addresses compared
| Method | Where it is stored | You can clear it? | Survives private mode? |
|---|---|---|---|
| Cookies | On your device | Yes | Cleared at the end |
| IP address | Seen by sites and networks | Change with a VPN | Yes |
| Fingerprint | Computed from browser details | No, but you can change the details | Yes |
A fingerprint does not store anything on your device. It is computed again at each visit, which is why clearing cookies does not remove it. Trackers often combine all three methods for a more stable picture.
What common browsers do about fingerprinting
- Tor Browser aims to make every user look the same, with fixed window sizes and a common font set.
- Brave adds small random changes to canvas, audio and some hardware values, so your fingerprint changes between sites and sessions.
- Firefox blocks known fingerprinting scripts in its stricter modes and has an optional setting that makes many values uniform.
- Safari limits some detail and reduces the fonts and hardware that pages can see.
- Chrome and Edge are working on privacy features, but by default they expose most of the details in the table.
Settings change quickly, so check the current documentation of your browser. Running this test before and after a change is the most reliable way to see its effect.
Privacy, limits and responsible use
The page reads standard browser details and shows them on your screen. No data leaves your device, and nothing is saved. A site can read all of these values without asking, which is the point of the test. The browser ID is only an example of how details combine and is not the ID any real tracker uses. Settings and browsers change often, so check the advice against your browser's current documentation.
Frequently asked questions
What is browser fingerprinting?
It is a way of recognizing a browser by combining many small details, such as fonts, screen size, graphics card and language, without using cookies.
How do I check my browser fingerprint?
Open this page and your browser's details appear in the table with a risk level for each. Press the button to check again.
Is anything uploaded?
No. The checks run in your browser, and the results stay on your screen unless you copy, download or print them.
What does the browser ID mean?
It is a short code made from your main details, to show how a site could turn them into one identifier. A different browser or setting gives a different code.
What are the bits?
Each bit roughly halves the group of people who share your value. Added together they estimate how identifying your details are. The values are illustrative averages from research.
Does this tell me if I am unique?
Not exactly. Real uniqueness depends on how many other people have the same setup. Use a research project with real visitor data for that.
What is canvas fingerprinting?
A page draws hidden text and shapes and reads the pixels. Small differences in fonts and graphics drivers make the result differ between devices.
What does a changing canvas result mean?
If it changes each time, your browser is adding noise to resist fingerprinting, as some privacy browsers do.
Why does WebGL matter?
It exposes the graphics card and driver, which are strong identifiers. Some browsers hide or generalize them.
Do fonts really identify me?
Yes. The list of installed fonts can be quite distinctive, especially if you added design or language fonts.
Will a VPN stop fingerprinting?
No. A VPN hides your IP address, but your browser details stay the same.
Does private or incognito mode prevent it?
No. It clears history and cookies when you close it, but the browser still shows the same details.
How can I reduce my fingerprint?
Use a browser with built-in protection, such as Tor Browser, Brave or Firefox with resist fingerprinting, avoid unusual extensions and fonts, and keep the window size standard.
Can protection make me more unique?
Yes. Unusual settings or add-ons that change only a few values can make you stand out. Built-in protection that many people share works best.
Is fingerprinting legal?
Rules vary. In many regions it counts as tracking and needs consent under privacy laws. Fingerprinting is also used for fraud prevention.
Why do sites use it?
For advertising, analytics, bot and fraud detection, and recognizing returning visitors who clear cookies.
Is it free?
Yes. It is free to use online with no sign-up.
Sources and further reading
- EFF, Cover Your Tracks (coveryourtracks.eff.org), research on browser uniqueness.
- Eckersley, How Unique Is Your Web Browser? (Electronic Frontier Foundation).
- Laperdrix et al., Browser Fingerprinting: A Survey (ACM Transactions on the Web).
- W3C, Mitigating Browser Fingerprinting in Web Specifications.
- Mozilla, Firefox Fingerprinting Protection and resistFingerprinting documentation.
Sources were consulted in October 2026. Standards and rules can change, so always check the official page for your situation.