Spotify has been saying it has more than 10m active users for a while now, but it appears the publicly-stated figure is due for an update. Evolver.fm has noticed that Facebook stats show 17.5m monthly active users for the streaming music service – and that’s a figure that doesn’t include users who have chosen not to connect Spotify to their Facebook accounts. That’s good growth for the service, although as Evolver.fm points out, it also brings down the estimated conversion rate for Spotify’s free-versus-paid users. 3m subscribers out of 10m active users is 30%, but if we’re talking 17.5m active users, it’s more like 17%. However, as the recent removal of some restrictions on its free service shows, Spotify and its label partners’ bet is that its free tier will convert more users over time – a large chunk of those extra 7.5m free users will still be in their six-month unlimited use periods.