Most privacy tools stop at your IP address. 404 goes deeper. Websites build a fingerprint of your device, allowing them to track you across time and build a profile of your online activity. This is done by tracking dozens of values: HTTP headers, TLS handshake, browser characteristics, and more. 404 is a local proxy that replaces your fingerprint with a consistent device profile. Built for journalists, lawyers, researchers, or anyone who believes their online behavior is their own business.