Hair amounts for other dolls
For bigger heads
For dolls with heads larger than 7 inches, we typically recommend using size 38" hanks for maximum length and versatility. But you can also opt to use the pre-cut hanks to root your doll if you only need a finished length of 9.5" or shorter.
A doll with a 10 inch head circumference:
Option 1: 10 x size 38" hanks with a finished length of 19"
Option 2: 2 x Gene Long with a finished length of 9.5"
Option 3: 2 x Gene Medium with a finished length of 4.75"
Recommendation for Blythe dolls: 2 Barbie size hanks or 6 size 38" hanks
Blythe dolls have a head circumference of 8", but they have very high foreheads, so they generally need only as much hair as a doll with a 6" circumference head would usually need, unless you're one of those people who likes to root their plugs really thickly. Therefore, a Blythe doll will need about 2 Barbie-size hanks or 6 size 38" hanks, depending on the finished length you want.
Recommendation for Patti Playpal dolls: 8 size 38" hanks
Patti Playpal dolls also have head circumferences of 8", but since Patti dolls are so tall, most people prefer to give them long hair, and most people like to use the 38" hanks, which result in Patti's hair being 19" long after she's been rooted. If you want Patti doll to have 19" long hair, you will need to buy eight 38" hanks to reroot her.
For longer hair
If you want rooted hair that is longer than 19 inches, you can consider using the knot method for rerooting to maximize the strand length. While rerooting with the knot method, you don't fold the hair in half and simply knot one end of the hair inside the doll's head. This allows you to use the full length of each hank to reroot the doll. Obviously, you would need to buy more hair to achieve this, but the plus side is that the doll's hair would be longer!