Neck -  Measure comfortably the distance around the neck.

Chest - Measure comfortably around the largest part of the chest behind the arms.

Length - Measure precisely the distance beginning just behind the head and to the base of the tail.
Apparel Sizing Chart

xxs-xs
chest: 10 -12 inches
neck:   6 - 8 inches
length: 7 - 8 inches

s-m
chest: 13 -16 inches
neck:   9 -11 inches
length: 9 -11 inches

l-xl
chest: 17 - 22 inches
neck:  12 - 14 inches
length: 12 - 16 inches
Created by Woofs & Whiskers.  All content, including pictures, is copyright 2009 and may only be used with permission.
Need help or have a measuring question? 
Email woofsandwhiskers@gmail.com for assistance.