Open Source JavaScript Browser Fingerprinting Software

ThumbmarkJS is an MIT-licensed browser fingerprinting library that produces stable fingerprints with 90% uniqueness. It works with normal and private browsing. ThumbmarkJS is a free, open‑source browser fingerprinting JavaScript library, designed as an alternative to FingerprintJS. It generates distinct, persistent device fingerprints using web APIs like canvas, audio, fonts, WebGL, and more, enabling identification of browsers across sessions, even in incognito or cleared-cache scenarios. It supports both client-side-only installs via CDN and npm, with optional API integration for improved uniqueness.

This project is a proof of concept that any website can identify and track you, even if you are using private browsing or incognito mode in your web browser. Many people think that they can hide their identity if they are using private browsing or incognito mode. This project will prove that they are wrong.