User blog comment:Pihou/How Many VOCALOIDs Sold?/@comment-53539-20140617081943/@comment-5051846-20140617173842

Yeah, as Angel touched upon, unless companies release figures (which they often don't), it's really tough to guess. What if people buy the Vocaloid and publish songs using it (afterall, it's also used for experimenting and demonstrating song lyrics)? We'd never know. orz

I don't think it's past a million, but not an insignificant amount for a usually niche software either. :D