We estimate the number of users by analyzing the requests induced by clients to relays and bridges.
This graph shows the estimated number of directly-connecting clients; that is, it excludes clients connecting via bridges. These estimates are derived from the number of directory requests counted on directory authorities and mirrors. Relays resolve client IP addresses to country codes, so that graphs are available for most countries. Furthermore, it is possible to display indications of censorship events as obtained from an anomaly-based censorship-detection system (for more details, see this technical report). For further details see these questions and answers about user statistics.
The following events have been manually collected in the metrics-timeline Git repository and might be related to the displayed graph.
|Dates||Places/Protocols||Description and Links|
Release of tor 0.3.2.8-rc, intended to fix the KIST bug that enabled a DoS on relays by running them out of memory.
geoip and geoip6 databases updated to "December 6 2017 Maxmind GeoLite2 Country" (
|2017-12-16 to 2017-12-17||Bridges Unknown||
Drop in the number of measured bridges.
graph mailing list post
|2017-12-12 to 2018-01-18||meek||
Outage of the meek.bamsoftware.com (unthrottled for public use), meek.bamsoftware.com:7443 (former meek-azure, now unused), and gaeuploader.meek.bamsoftware.com (used by GAEuploader) bridges.
|2017-12-10 to 2018-02-01||Germany <OR> Relays Unknown||
Further, slow increase of relay users in Germany, from 500k to over 1.5M.
graph Reddit thread ticket
|2017-12-08 to 2017-12-11||Bridges||
The bridge authority was down for unknown reasons.
graph mailing list post
This material is supported in part by the National Science Foundation under Grant No. CNS-0959138. Any opinions, finding, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. "Tor" and the "Onion Logo" are registered trademarks of The Tor Project, Inc.. Data on this site is freely available under a CC0 no copyright declaration: To the extent possible under law, the Tor Project has waived all copyright and related or neighboring rights in the data. Graphs are licensed under a Creative Commons Attribution 3.0 United States License.