Research Tools

If you’re interested in performing research relating to Tor, you might find the following tools useful. Always ensure that the research you are performing is safe.

Test Networks

New design proposals and attacks on Tor are challenging to test in the live network due to deployment issues and the risk of invading users’ privacy. The following tools allow you to easily run a test Tor network, isolated from the live public network, that you can safely perform experimentation on.

You might also choose to build a testing network manually, or using your preferred configuration management tool. See the testing network options of the tor configuration file for more details.

Path Selection

The relays chosen for a path through the Tor network require tradeoffs to be made between anonymity, performance, and other properties.


A controller allows applications to interact with Tor. This happens via the Tor Control Protocol. Various events such as circuit creation and bandwidth counts will be able to be read from the Tor process. Commands can also be given to change the configuration of the Tor process or to instruct it to perform tasks.

Descriptor Libraries

The following libraries help you with parsing and generating Tor network related data formats. Descriptors may be obtained either from a directory authority, directory cache, local client or the CollecTor service:

Add your tool

If you have developed a tool that may be useful to other researchers working on Tor, then please send a mail to with the details you would like to have added.