The #Fediverse makes it big time:
"1,247,408,216 Users"
per https://the-federation.info (archived: https://archive.today/2023.09.03-214325/https://the-federation.info) :P
Alternative interpretation: the-federation.info has a bug in its statistics right now. After all, other estimates are 100 times lower:
* https://fediverse.observer/stats
* https://fedidb.org
* https://fediverse.party/en/fediverse
