Although it looks easy, measuring the height of a horse for certification can be fairly tricky. Traditionally, a horse’s height was measured in hands. Starting from the ground, you used the width of your hand (later standardised at 4″ or 10,16cm) to measure the distance from the ground to the top of a horse’s withers.
Thus, your horse might be 15 hands high (hh). If he was taller than 15 hands, but shorter than 16 hands, you would estimate the number of inches remaining above the last hand measured. For example, if you measured 15 hands and there was still about 1″ (2,54cm) to the top of the withers, the height of the horse was determined to be 15,1hh. When South Africa joined the sane part of the world and switched to the metric system, the unit of measurement for horses changed to the centimetre. So a horse 11,3hh at the withers would be certified as 120cm.
The height is measured from the ground to the highest point of the wither. Photo courtesy of Lisa Kohlberg: Realpix
The height of competition horses needs to be certified and should be exactly the same if measured by two officials at two different times. To ensure this level of accuracy, the horse must be stood on a level surface such as a concrete driveway, with both its front feet together. Its head should be in a natural position, but slightly raised, as the height will be slightly less if the head is lower than the withers.
The height is measured using a measuring stick with a spirit level in the cross arm. The stick is placed with the bottom end on the ground, a few centimetres to the side of the horse’s leg, just behind the heels (as seen on the right). The cross arm is gently lowered until it touches the highest point of the withers, then gently angled back and forth until the spirit level bubble is centred. This should allow you to measure the horse in both hands and centimetres, as both are marked on a standard measuring stick.
Because accuracy is crucial, officials are expected to pass a course in measurement of horses and only an accredited official may fill in the measurement in a horse’s passport. Officials permitted to measure horses are also expected to confirm the identity of the horse as stated in the passport as well as confirm the microchip, although the latter is not yet obligatory.
The official must also certify whether the horse is shod or not, as this allows for an extra centimetre to be added to the height. The age of the horse further affects its height: the animal usually attains its greatest height after six or seven years, so the age is also reflected in the height certificate.
Why it’s important
The height of a horse can affect its performance. In dressage, horses less than 150cm (more recently 148cm) at the withers,
are classified as ponies and ride in a smaller ‘pony-sized’ dressage arena, as their stride is much smaller than that
of larger horses. Jumpers are also subdivided into ponies and horses, with a similar cut-off point in wither height. An important reason for this differentiation is that judging can be difficult if horses vary significantly in size in the same arena, so horses are subdivided by height at shows.
There’s also a cut-off size for ponies used in lead rein classes, where the riders are small children.