How many sims can you handle at once in a household?

8. I think almost every household I have in my game has 8 sims, though usually 1-2 are pets which don't require much time put into them anyway. I guess in a way that means I can only really handle 6, but I do have this one house of 8 all of which are humans, and it's literally my favorite family and I can handle all of them fine so I'll still go with 8.