We report on a variety of ways the Tor network is used and its performance on our open source Metrics portal: https://metrics.torproject.org. The data here is designed to be reproducible such that anyone can investigate the our claims about the Tor network's usage, speed, relays, countries of impact, and other factors.

Beyond metrics on the network, our User Research and Community teams work regularly to survey, meet with, and build relationships with Tor users in order to better understand their needs and whether or not we're meeting them. We report regularly about these efforts on our blog, e.g.: https://blog.torproject.org/empowering-human-rights-defenders/.