What is Tor?

Tor is a free network that anonymises your internet traffic. It started as a US Naval Research Lab project in the 1990s, became a non-profit in 2006, and is now used by millions of people every day — journalists protecting sources, activists in hostile regimes, ordinary users who simply don't want to be tracked.

The name is a retronym: The Onion Router. The "onion" refers to layers of encryption wrapped around your traffic, peeled away one relay at a time so no single party sees both who you are and what you're requesting.

How onion routing works

When you visit a site through Tor, your request is wrapped in three layers of encryption and sent through a randomly chosen circuit of three volunteer relays:

1. The guard relay knows your IP address, but can't read your traffic or know the destination.
2. The middle relay sees only two other relays — neither you nor the destination.
3. The exit relay can see the destination and the unencrypted traffic (if the site isn't using HTTPS), but has no idea who you are.

Each relay peels one layer of encryption. That's the onion. No relay has the full picture, and your circuit is rotated every few minutes.

The Tor Browser

The Tor Browser is the easiest way to use Tor. It's a modified Firefox that:

• Routes every request through the Tor network by default.
• Disables trackers, fingerprinting-heavy APIs and third-party cookies.
• Ships with a security slider so you can disable JavaScript and other risky features in one click.
• Resolves .onion addresses natively — addresses that don't exist on the normal DNS.

Download it from torproject.org and verify the PGP signature if you can. On mobile, the official Tor Browser exists for Android, and Onion Browser is the recommended option on iOS. The dark web browsers guide compares all the options — Tor Browser, Onion Browser, Brave's Tor mode, Tails and Whonix.

What are .onion addresses?

An .onion address doesn't exist on the public DNS. It is, literally, a cryptographic public key — a 56-character string followed by .onion. When you type it, Tor establishes a connection to a server that has proven it holds the matching private key.

This gives you two guarantees regular websites can't match: you know you're talking to the real operator (because the address is their public key), and the server never learns your IP. That's why newsrooms, messaging apps and whistleblowing platforms run them.

You can browse a list of well-known, verified onion services on the dark.cfd directory.

Who runs the Tor network?

Tor itself is maintained by the Tor Project, a non-profit funded by a mix of grants, donations and government contracts (historically including the US State Department's human rights division). The relays that actually carry traffic, however, are run by thousands of volunteers and organisations around the world. No single entity controls the network — which is a feature, not an accident.

Limits you should know

Tor is powerful, but it's not magic. A few honest caveats:

• If you log into an account tied to your real identity, no amount of relays will keep you anonymous from that service.
• Exit relays can read unencrypted traffic. Always prefer sites with HTTPS, or use .onion services where the encryption extends end-to-end.
• Torrenting and running background apps over Tor often leaks your IP through side channels. Don't do it.
• An adversary that controls both ends of your circuit can, in theory, correlate timing. In practice this is hard, but it's why people stack Tor with careful operational security for high-stakes use.