A horse's halter is the piece of equipment that wraps around the head of the animal. In generally lays across the sides of the horse's face and wraps around the bottom of the chin, near the throat, and upward around the back of the ears. It is used for control purposes, generally having a ring at the bottom near the chin, where the animal's handler can clip in a lead line. This equipment aids in keeping both the animal and the handler safe and secure. A horse's halter should fit securely but not loosely. Determining the proper fit will help keep your animal safe.
Consider what material you want for your horse's halter. The fabric may affect how much the halter can stretch. Horse halters are often made of a fabric blend of cotton and nylon or a leather material. Although fabric blends tend to be cheaper and can potentially be softer on the animal, many owners prefer the durability of leather.
Shop by "hands size." Horses are measured in hands, and many retailers of halters will state a "hands size" that the equipment will fit. For example, a pony of 14 hands will fit a halter advertised as size 12 to 15 hands. If you don't know your animal's size, measure in inches from the ground to the horse's withers -- the area between the neck and the back, where there is a small, bony protrusion. Each hand is equal to 4 inches, so divide the number of inches for your horse by four and you will have its "hand size."
Measure your horse's specific halter size. Some halters are sized by a measurement from cheek to cheek, going up around the ears. Using the measuring tape, start at the left cheek and follow a straight line up to the ears, then back down to the other cheek. This will give you an approximate size in inches, and some halters are sold by this size system.
Shop by breed. Often, certain horse breeds have general characteristics, such as head size, and halters are sized according to these breeds. You may find equipment retailers who note a halter size as "for Arabians" or "for quarter horses." Often, these halters will fit most horses of that breed. In addition, they are likely adjustable for small discrepancies.
Adjust the halter to your horse's specific fit. Most halters have small buckles that allow you to choose a hole that tightens or loosens the fit. Make the halter snug to the horse's face but allow enough space to insert two fingers between your animal's face and the equipment. This keeps the halter tight enough for safety, but loose enough for your animal's comfort.