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.
The manually collected events in this table do not necessarily match the automatically generated possible censorship events shown in the graph.
|Dates||Places/Protocols||Description and Links|
Increased the file descriptor limit on default obfs4 bridges ndnop3 and ndnop5 from 4096 to 32768. They had been failing bootstrap attempts from a test location in the U.S. about 40% of the time.
graph showing failed connections
geoip and geoip6 databases updated to "June 8 2017 Maxmind GeoLite2 Country" (
Tor Browser 7.0 released. Adds an IPv6 address for default obfs4 bridge Lisbeth. Adds new default obfs4 bridges frosty and dragon.
blog post IPv6 ticket frosty and dragon ticket
mailing list post
|2017-05-23 to 2017-06-13||obfs4||
Default obfs4 bridge LeifEricson rejects connections due to a broken firewall forwarding rule. This didn't affect the bridges "real" obfs4 port, but it did affect the port at that time configured in Tor Browser.
|2017-05-10||Egypt <OR> Relays Unknown||
Drop in direct users from Egypt.
tor-talk post graph
geoip and geoip6 databases updated to "May 2 2017 Maxmind GeoLite2 Country" (
mailing list post
The meek-amazon bridge upgrades to meek-server 0.27.
|2017-04-20||meek obfs4 scramblesuit||
Tor Browser 7.0a3 is released. It changes the
Tor Browser 6.5.2 is released. It changes the
blog post comment about app.update.url
|2017-04-14 to 2017-08-20||<OR>||
Directory authority maatuska's bwscanner stops operating, leading to a drop in traffic on some relays.
tor-consensus-health post about start tor-consensus-health post about end tor-dev thread analysis
geoip and geoip6 databases updated to "April 4 2017 Maxmind GeoLite2 Country" (
Orbot 15.4.0 beta-2 multi is released, containing the new meek-azure CDN configuration.
mailing list post commit
|2017-01-25 to 2017-04-05||webstats||
Tor Browser update pings roughly halve. The beginning corresponds with the release of Tor Browser 6.5.2, which changed the
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.