Diapers!

Hey ladies! I'm a FTM (little boy due any day now) and they are estimating him to be on the smaller side between 6-7 pounds. I'm curious about how long your little ones stayed in newborn diapers? I got tons of size 1's but not many newborns and I want to make sure I have enough for those first couple of weeks so I'm not constantly sending someone to the store for more.