Tor (network)

Tor
DeveloperThe Tor Project
Initial release20 September 2002 (2002-09-20)
Stable release(s) [±]
0.4.9.5  (12 February 2026 (12 February 2026))
s
Preview release(s) [±]
Written inC, Python, Rust
Operating systemUnix-like, (Android, Linux, BSD, macOS), Microsoft Windows, iOS
Size150-231MB
Available inEnglish
TypeOverlay network, mix network, onion router, Anonymity application
LicenseBSD 3-clause license
Websitetorproject.org
Repository

Tor is a free overlay network for enabling anonymous communication. It is built on free and open-source software run by over seven thousand volunteer-operated relays worldwide, as well as by millions of users who route their internet traffic via random paths through these relays. This technique is called onion routing.

Using Tor makes it more difficult to trace a user's internet activity by preventing any single point on the internet (other than the user's device) from being able to view both where traffic originated from and where it is ultimately going to at the same time. This conceals a user's location and usage from anyone performing network surveillance or traffic analysis from any such point, protecting the user's freedom and ability to communicate confidentially.