In this announcement, we are told that
Now, Stack Overflow for Teams has a free tier for up to 50 users, forever.
Is that current users? Or total users?
I ask because I am associated with an organization with a high turn over. If that's total users, meaning up to fifty people can be given access and the fifty-first triggers a requirement to pay, there's no point in us considering it. We'd end up with forty-eight inactive users, two active users, and about ten people who should have access but wouldn't be able to get it. However, if that's fifty users at one time, then we might be a good fit. I don't think we've ever had as many as twenty simultaneous users.
By simultaneous users, I mean users who currently should have access even if they are not currently connected. So someone who is asleep and has their computer turned off would count against the limit if they were able to wake up and access the team site. But those who have left the organization would not count after we removed their access.
We currently use a project tracking system that supports up to ten users that way and that mostly works (although ten is a bit tight). And we previously used a wiki system that supported fifteen total users, which is why we absolutely won't do that again.
I'm assuming that if the organization ever gets out of the startup phase, it will have reason to move to a paid account. Possibly because it would then need more than fifty users. And possibly because there are other advantages.
I tried looking for documentation of what fifty users actually means, but there doesn't seem to be a definition here nor a link to further documentation.
All other tiers are priced on a per seat basis and can be monthly or annual payment structure.
I can't determine if that means that the free tier is not on a per seat basis or if it is. And again, it's not clear that that is current seats, although I would expect it is. But even so, that still doesn't tell me anything about the free tier. As that statement is only about the non-free tiers.