

I want to conclude with a few words of caution. So, of our user base (roughly 300 Million), perhaps about 100 Million people use at least one add-on.Balancing these two issues (i.e., they may come close to offsetting), I think it’s safe to say that roughly 33% of Firefox users (32.8/100) have at least one add-on.There are a couple issues at this point: (1) There could be multiple users from the same IP address, and (2) There could be a handful of add-ons where adoption isn’t fully user-initiated (e.g., people happen to have it, but don’t know what it is).We saw Firefox add-on pings from 32.8 Million unique IP addresses.Narrowing our focus to just a single day’s worth of data (we simply picked June 22nd), we turned our attention to estimating add-ons usage for just that one day, so that we could compare something on a relative basis to our overall Fx metric of 100 Million active daily users.We know that there are roughly 300 Million Firefox users, and on a given day, we see about 100 Million active users of Firefox.Here’s my thought process for the important data points Simon’s been able to extract: Thanks to some recent work by Simon Krueger, our metrics intern, we’ve been able to arrive at a rough approximation.

There’s a relatively simple question we’ve been asking for quite some time… of the total Firefox user base, how many people (or what percentage) use at least one add-on?
