Estimating Foal’s Mature Height: More Art Than Science

How big will that foal be when it’s fully grown? Mature size is influenced by nutrition, health history, breed, and the foal’s genetics, among other factors, but a rough estimate of adult height can be gotten by using a measuring tape.

To get an idea of mature size, stand the young foal squarely on a level surface (this will go much more smoothly if the foal has been halter-broken, leads well, and is controlled by a helper). Hold one end of a tape at the foal’s elbow and measure the distance to the ground. Double this measurement and you have an idea of how tall the mature horse will be.

For a weanling that is four to six months old, measure from the elbow to a point about halfway between the ground and the young horse’s fetlock. Double this measurement to get the weanling’s final height.

When using this method on a yearling horse, measure from the elbow to a point about one-fourth of the way from the fetlock to the ground, and double this measurement.

If you don’t want to go to the trouble of measuring the foal’s legs, you can get some idea of how the horse will size up by looking at his sire, dam, and full siblings. Probably the young horse will reach a mature height similar to his full siblings, assuming all have been fed and managed in the same way. However, the only certain way to tell is to wait until the horse is fully grown at about four to five years old. Pony breeds tend to reach mature heights somewhat faster, with Warmblood breeds needing an extra year or two to gain their full growth.

Wondering how your foal compares to others? Gro-Trac® is the first equine growth-monitoring software that allows breeders to compare the growth rates of their stock with those of young horses of similar age, sex, and breed.