What do large-scale studies (e.g. FAU Erlangen-Nürnberg) reveal about how common and stable browser fingerprints are?

About 99.5% of browsers carry a uniquely identifiable fingerprint — not merely "a fingerprint" (every browser has one of those), but one distinct enough to single that browser out — and these fingerprints stay stable for roughly 6–8 months, long enough for sustained tracking.

Key research findings:

• 99.5% of browsers are uniquely identifiable by their fingerprint — i.e. the combination of attributes (user agent, fonts, canvas/WebGL, screen, plugins…) is distinctive enough to distinguish them from nearly every other browser. The point isn't that a fingerprint exists; it's that it's almost always unique.
• Fingerprints stay stable for 6–8 months (config rarely changes that fast)

Emerging research trends:

• AI-based detection — machine learning improves fingerprinting accuracy
• Cross-device linking — connecting desktop and mobile profiles of the same person
• Network fingerprinting — identification via network-level properties

Tools to test your own fingerprint:

• AmIUnique.org — compares your fingerprint against millions of records
• BrowserLeaks.com — comprehensive suite (IP, DNS, Canvas, WebGL, Fonts)

Tip: Because fingerprints are stable for months but do drift over time, trackers combine them with other signals to keep continuity — which is why isolated defenses are insufficient.