Using a soft tape measure, begin measuring at the widest part of your pup's neck (for most dogs, this will be nearest their shoulders). Place two fingers perpendicularly between your dog's neck and the tape measure to ensure a comfortable fit.

Next, use the soft tape measure to measure at the widest part of your pup's chest (for most dogs, this will be at the middle of their rib cage). Place 2 fingers perpendicularly between your dog's body and the tape measure to ensure a comfortable fit.