So, if you are looking for the right length for your child, as you may have noticed from the table in the picture above (the tennis racket length chart), you should choose: A 19-inch racket length if your child is four years old or younger. A 21-inch racket if your child is 4-5 years old. A 23-inch racket if your child is 6-8 years old.
https://tennisracketball.com/guide/tennis-racket-size