How exactly are concurrent users determined for a Firebase app?

How exactly are concurrent users determined for a Firebase app?

It seems in the analysis panel that there are more peak concurrent users than I have had browser windows open using my app.

I'm a little worried about committing to FB for the future with the 1000 concurrent limit, but perhaps I'm overestimating the popularity of my app and likelihood of ever reaching that limit. :)

A concurrent user is a single client (browser tab, mobile app, Node.js process, etc) connected to Firebase at a time. If you have 3 browser tabs open, you should see 3 concurrent users (note that the stats in our analytics dashboard are a little bit delayed).

In our experience, on average, 1 concurrent user is equivalent to ~1400 visits per month to a website. 1000 is a very large number of concurrent users for most apps, and fewer than 1% of Firebase apps ever reach this.

Note that Firebase is capable of powering apps well beyond 1000 concurrent users, so if you have a bigger app (even a much, much bigger app), it's not a problem.