The handle plays a key role in how well your racket fits into your hand. It also determines where the center of mass of the racket is going to be. The size of the handle is somewhat adjustable, but with many layers of cloth or rubber, one may not be able to feel the bevels of the handle and thus it is advisable to get a bigger handle instead. The size of player’s hand and the size of a comfortable grip for that hand are closely correlated. As a rule of thumb, select a handle as shown in the figure. Handles come in about 4 different sizes, usually denoted by a number appended to G, like G2 or G4. In my experience, it is not very easy to remember the sizes because of various reasons. Rather, I would suggest that you check different rackets for their handle sizes and when it feels right, take it to the court for a game, and test whether your conviction is a lasting one. You can follow my handle-hand size guide also, but nothing beats the hand-feel test.