- Bluesky: 15,128,928
- Mastodon: 15,499,978
Source: https://bsky.jazco.dev/stats and https://mastodon.social/@mastodonusercount
These numbers are to taken with a grain of salt. Mastodon in example can’t count all instances, because not all are federated. Also on both instances we don’t have numbers of active users per day or logged in at the same time. However Bluesky provides statistics beyond just the number of accounts. I’m not saying one is better or has more active users than the other, only that the total number of accounts can be misleading as much as the Megapixels count of your camera.
Edit: I forgot there is another statistics displaying the number of active users for Mastodon: above 2.5 million users. Also it displays current Mastodon user count less than 10 million. Again either it counts it differently or it does not have access to the same instances as the other account has. Source: https://mastodon-analytics.com/
At least BlueSky is built on a technology based on open standard protocol and is decentralized. Kind of similar to the goals of Fediverse / Mastodon. So I assume someone else can just create a server and join the network of BlueSky? I don’t know if this is possible. But in reality at the moment its controlled by only one big company.
My hope is that they will one day cooperate with Fediverse, so it becomes read from and write to relationship.