Tribler offers anonymous downloading. Bittorrent is fast, but has no privacy. We do NOT use the normal Tor network, but created a dedicated Tor-like onion routing network exclusively for torrent downloading. Tribler follows the Tor wire protocol specification and hidden services spec quite closely, but is enhanced to need no central (directory) server.

Developers only: Tribler Anonymity Specification (for all details)


Do not put yourself in danger. Our anonymous download feature is not yet broadly tested.

Anonymous downloading is a new feature, barely a year old. We are sharing the design and code so that the community can test and evaluate it. This helps us make sure that it’s as secure as it needs to be before people start relying on it.

How it works

Bittorrent Swarm

Bittorrent offers no privacy protection. It is easily traced that you are downloading certain (controversial) content. Content is offered openly and everybody can see who is doing what. Dissidents and unpopular opinions can be easily discovered and subsequently stopped.

One proxy layer

All downloads now go through other computers. All direct contact with the Bittorrent swarm is gone. The proxy layer is simply a set of computers that relay messages between you and the Bittorrent swarm. However, you need to fully trust all these selected proxies, they can see exactly what you download. The proxies encrypt the data, only you can read it.

Three proxy layers

Adding three layers of proxies gives you more privacy. Three layers of protection make it difficult to trace you. Proxies no longer need to be fully trusted. A single bad proxy can not see exactly what is going on. The first proxy layer encrypts the data for you and each next proxy adds another layer of encryption. You are the only one who can decrypt these three layers correctly. Tribler uses three proxy layers to make sure bad proxies that are spying on people can do little damage.

The hidden seeder

Seeders are unprotected in the above steps. This version of Tribler includes experimental support for hidden seeding. Uploading is just as anonymous as downloading with hidden seeding. We now automatically add proxy layers for seeders, similar to steps 2 and 3 above. The beauty of hidden seeding is that it can encrypt the content already in such a manner that only the downloader can read it (end-to-end encryption). This creates a darknet that is quite safe. However, we still need to enhance hidden seeding with features to improve the traversal of NAT boxes, now they lower the speeds significantly.

Read the specifications.

Tribler anonymity test

The anonymity test, active in the "Downloads Section" is shown. It starts automatically in 5 minutes. Note the anonymous download speed of 1.5 MByte/second using only 4 connections. The anonymity tab in the lower torrent details shows more details such as active and created (2 out of 3 hops) circuits. Only the Internet address of the first hop in circuits is shown, others are known only by their public key.

We now support a subset of the TOR onion routing protocol. Our custom onion network is enhanced to allow everyone to function as a relay. Even people behind a restrictive NAT box can join and help others protect their privacy. Hidden services for seeders is also supported (experimental). For full details read the Anonymous Protocol page for developers.