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Anti-fingerprinting browser: choose protection that fits your browsing
Compare Firefox's built-in and advanced fingerprinting protection, check site compatibility, and learn what privacy tests can prove.
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For everyday anti-fingerprinting protection, Firefox's built-in Enhanced Tracking ProtectionOpens in a new tab is a documented starting point. Its Strict mode adds protection against suspected fingerprinters outside private windows. Mozilla recommends the built-in approach for most usersOpens in a new tab instead of advanced Resist Fingerprinting settings, which can make sites behave incorrectly.
In short:
- Built-in comes first. Mozilla recommends Firefox's built-in protection for most users.
- Strict adds coverage. It protects against suspected fingerprinters in normal windows too.
- Profiles aren't anonymity. Anti-detect browsers serve separate-profile workflows, not proven anonymous browsing.
Which protection fits your browsing
Browser fingerprinting uses browser settings and characteristicsOpens in a new tab to help recognize a browser. Anti-fingerprinting controls aim to make that tracking harder. Anti-detect tools serve a different task by giving separate profiles different presented identities.
Choose by your browsing task and the website changes you can accept.
| Browser choice | Documented control | Main tradeoff | Keep it if |
|---|---|---|---|
| Firefox ordinary browsing | Known-fingerprinter protection | List-based coverage has limits | Your needed sites work and this coverage fits |
| Firefox Strict or Private Browsing | Known and suspected protection | Check needed website features | You want the added coverage |
| Firefox advanced protection | Resist Fingerprinting | Broader website behavior changes | You accept those changes on needed sites |
| Anti-detect: Donut BrowserOpens in a new tab | Different fingerprint for each profile | Profile separation isn't proof of anonymity | You need separate profile identities |
| Anti-detect: IncognitonOpens in a new tab | Isolated profiles with unique fingerprints | Profile separation isn't proof of anonymity | You need its profile-management workflow |
If Firefox already meets your needs, check its built-in mode before switching browsers or enabling advanced settings. Strict is the documented choice when you want suspected-fingerprinter protection in normal windows, not just private windows.
Donut Browser and Incogniton document distinct fingerprints for profile workflows. Those vendor claims don't prove anonymity or establish stronger everyday tracking protection. The Firefox recommendation is a supported starting point, not a best-browser ranking across all privacy-focused options.
Check which Firefox settings are on
Use a desktop Firefox profile you control, and record its original mode so you can restore it. These steps follow Mozilla's desktop documentation. Check the controls in your installed version instead of assuming every release or mobile app matches.
1. Open Settings and find Enhanced Tracking Protection.
Note the selected protection level before changing it. You should see the active level in Settings. That confirms the configured mode, not that every fingerprinting attempt is blocked.
2. Choose the window coverage you need.
Mozilla documents known-fingerprinter protection in ordinary browsing. Private Browsing and Strict mode include both known- and suspected-fingerprinter protection. Select Strict if you want suspected-fingerprinter coverage in normal windows while keeping the built-in approach.
3. Check Custom settings if you need finer control.
Custom exposes separate Known fingerprinters and Suspected fingerprinters controls. Check the window scope shown for suspected protection, and record whether it covers private windows or normal windows too. If the controls differ from the documented arrangement, record what your installed version shows before making assumptions about coverage.
If advanced settings may already be active
Mozilla's Configuration Editor guidanceOpens in a new tab is for experienced users: changing advanced preferences can affect browser stability, security and performance. Inspect the existing values first, and change them only if you understand the effects and can restore the original configuration.
Inspect privacy.resistFingerprinting and privacy.resistFingerprinting.pbMode in about:config, and record both values before changing them. An extension can control these preferences.
Don't enable them as the default recommendation for everyday browsing. Mozilla warns that enabling Resist Fingerprinting only through its private-window preference can still cause some effects in normal windows. That setting doesn't fully separate all behavior by window type.
Check the sites you need before switching
Try Firefox's built-in controls first, then consider advanced Resist Fingerprinting only if its tradeoffs fit your tasks. Mozilla warns that advanced protection can make websites behave strangely even when it's working as intended. Built-in protection can also affect some image and video effects, including greenscreen effects and progressive drawing.
For each worksheet run, record your browser version, operating system, window type and protection mode above the table. Include the advanced preference values if Resist Fingerprinting is active. Use a separate copy for each configuration so you don't mix results.
Fill in this worksheet with your own sites and results.
| Site or task | Expected behavior | Observed result | Keep or restore |
|---|---|---|---|
| Scheduling and time zones | Correct dates and local times | ||
| Image editing or uploads | Needed uploads and effects work | ||
| Language and fonts | Expected language and readable text | ||
| Games or input devices | Needed controls respond correctly | ||
| Accessibility display preferences | Your needed display choices work |
These rows are checks, not predictions that every mode will break those features. Repeat the same task after each protection change, and keep the mode only if its effects fit your needs. A successful upload doesn't prove every image effect works, so check the feature you actually use.
Fix a broken site without changing every site
Change only a profile you control, and keep its original settings so you can restore them. For built-in Enhanced Tracking Protection, a site-specific check lets you investigate without lowering protection everywhere.
1. Open the site's tracking-protection panel.
Use the tracking-protection control beside the address bar while you're on the affected site.
2. Temporarily turn off Enhanced Tracking Protection for that site.
Use the panel's site-specific toggle. This disables Enhanced Tracking Protection for that site, not just its fingerprinting controls. Other sites retain their protection.
3. Repeat the same failing task.
If the task now works, the result points toward an Enhanced Tracking Protection interaction. It doesn't isolate the suspected-fingerprinter component. If the task still fails, restore the setting and investigate another cause.
4. Restore protection after the check.
Turn Enhanced Tracking Protection back on for the site. Record the outcome in your worksheet before deciding whether a lasting exception is worth the reduced protection there. A site-specific problem isn't a reason to lower protection for every website.
Keep advanced Resist Fingerprinting separate from this check. An Enhanced Tracking Protection exception doesn't tell you that advanced protection is off. If Resist Fingerprinting is active, inspect its preferences and any extension that controls them before making a separate change.
Read privacy tests without treating them as proof
EFF's Cover Your TracksOpens in a new tab checks simulated tracker blocking and compares your browser's fingerprint with recently observed visitors. Those are different measurements. A score describes that test's conditions and comparison sample; it doesn't prove that your browser is anonymous or untrackable across the web.
Label any result you record with the browser version, operating system, settings, window type, extensions, test method, date and network route. The network route means which connection you used. Compare the same method before and after one change, with other conditions kept unchanged. If a test doesn't explain its method or comparison group, don't infer how distinctive your browser is across the wider web.
Internet Protocol (IP) address privacy and browser fingerprinting are separate checks. Changing your network route doesn't show that browser-exposed fonts or canvas output, the image data your browser draws, have changed. Mozilla also warns that list-based blocking doesn't cover companies absent from the list, and some exceptions preserve website compatibility. Treat a test result as evidence about what that method measured, not proof that you can't be tracked.