The Ideal Toy Company marked the Toni dolls according to their size. To find the marking on the doll, look on the back of the head below the hairline and on the upper back of the doll’s torso.
When buying clothing for the doll, look for sizes listed by the number. The smallest is the P-90 that is 14 inches, while the largest is the P-94 at 23 inches tall.
When you are replacing parts on a Toni doll, you will need the doll number to get the right size leg, arm, or head.
Take a look at the Doll Reference page about Toni dolls. It shows some of the original dresses from the 1940s and 1950s.
Here are examples of Toni dolls and their outfits with the P-90, etc. designation included in the ad. These are on the Etsy site.
My sister has the larger doll, a P-91.