Comment by costco

There is no threshold. This site does not make any call as to whether a user is an alt or not. It just gives the users with the most similar word choice and from there it is up to you to decide (is there a very specific detail that both accounts mention, do they post at similar times, etc). I will say bolded accounts are substantially more likely to be alts though. But obviously it is not guaranteed that every user has an alt.