How can users test their browser fingerprint before and after enabling DuckDuckGo defenses?
Executive summary
You can measure your browser fingerprint before and after enabling DuckDuckGo’s protections by running established fingerprint tests (for example EFF’s Cover Your Tracks) and comparing metrics such as “uniqueness” or whether the test reports a randomized/non-unique fingerprint; independent testing shows DuckDuckGo’s browser/extension can move results to “strong protection” or non-unique in some tests (EFF/PrivacyTests reported strong protection for DuckDuckGo) [1]. Debate exists about whether DuckDuckGo ever used canvas/DOMRect APIs that triggered fingerprinting alarms in 2018–2019; DuckDuckGo denied fingerprinting and said detections were false positives tied to layout APIs [2] [3].
1. How to test your fingerprint: use known public tools
Run the same, reputable fingerprinting pages before and after enabling DuckDuckGo’s defenses — notably the EFF “Cover Your Tracks” test and PrivacyTests.org-style suites cited by reviewers and labs; these tests report on uniqueness, which APIs are being queried, and whether the browser appears to randomize or mask values [1]. Use the identical browser profile, same device and network, and capture screenshots or exported results so you can compare whether the test reports “strong protection,” “unique,” or “randomized” before and after [1].
2. What to look for in results: metrics that matter
Focus on whether a test marks your fingerprint as “non-unique” or “randomized” and which vectors change: canvas, fonts, audio, WebGL, plugins, and timezone. PCMag and PrivacyTests.org use EFF’s Cover Your Tracks to classify protection strength; in published comparisons the DuckDuckGo standalone browser and its extension raised Chrome’s score to “strong protection” and produced a non-unique fingerprint in their runs [1]. Changes in those categories are the concrete signals that DuckDuckGo’s defenses are affecting fingerprint surface area [1].
3. How to run a controlled before/after experiment
Use one browser profile and clear all caches/storage between runs if you want to test only the effect of DuckDuckGo’s feature. First, run the fingerprint test with DuckDuckGo protection off (or not installed). Record the test output that lists tracked APIs and the uniqueness assessment. Then enable DuckDuckGo’s browser or extension and re-run the identical test on the same machine and OS version. Document any shift in the badge (“strong protection” / “non-unique”) and specific API changes reported by the test [1].
4. Limitations and false positives you must expect
Fingerprint detection libraries and third‑party tests can create false positives because they don’t distinguish between “good actor” uses of APIs (layout or functionality) and malicious fingerprinting; DuckDuckGo argued this point when forum posts and add-ons reported canvas/DOMRect calls in 2018–19, saying those were layout APIs (getBoundingClientRect) and not fingerprinting, and denied any fingerprinting practice [2] [3]. That means a change in a single API readout doesn’t always equal privacy harm — cross-check multiple metrics and test suites [2] [3].
5. What reporting and community evidence shows about DuckDuckGo
In the 2018–2019 episode, community tools and forum posts flagged use of canvas/DOMRect APIs and some users reported unique fingerprints; DuckDuckGo responded that those were false positives tied to layout code and reiterated they do not do fingerprinting, citing their privacy policy and public statements [2] [3]. More recent privacy reviews and aggregated tests (PCMag/PrivacyTests.org) show DuckDuckGo’s products can achieve “strong protection” and non-unique fingerprints in EFF-style tests, indicating the company’s defenses do mitigate many fingerprinting vectors in practice [1].
6. Alternative viewpoints and residual risks
Independent reviewers note DuckDuckGo blocks many third‑party trackers but may not stop every first‑party technique or highly sophisticated fingerprinting; some fingerprinting techniques remain difficult to fully eliminate because they exploit browser characteristics browsers inherently expose [4] [1] [5]. Privacy testing projects warn that fingerprinting remains common and evolving, so “strong protection” in a given test does not guarantee total anonymity on the web [1] [5].
7. Practical checklist to run your test today
1) Pick EFF’s Cover Your Tracks (used by PCMag/PrivacyTests) as your primary test [1]. 2) Run it with DuckDuckGo off/disabled, save the result. 3) Enable DuckDuckGo browser or extension, repeat the exact test and compare the uniqueness flag and API list [1]. 4) If you see canvas/DOMRect reads flagged, remember DuckDuckGo has publicly said those calls can be legitimate layout functions and were the source of past false positives [2] [3]. 5) Repeat across multiple sites/tests to triangulate [1] [5].
Closing note: available sources do not mention a single definitive industry-standard metric that proves “fingerprinting eliminated forever”; tests report comparative protection and can produce false positives, so a cautious, multi-test approach is the only defensible method for users [1] [2] [3] [5].