Miniature horses have become increasingly popular in recent years, from horse enthusiasts and pet owners to people with disabilities in need of a guide animal. Their friendly, calm personalities, long lifespans, and of course their tiny size make them excellent companion animals.

But what exactly is a miniature horse?

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In a recent piece that highlighted some surprising facts about horses, I mentioned that many people consider miniature horses and ponies to be different. But as that story point outs, "Any horse that is shorter than 14.2 hands, or 58 inches tall at the withers, is considered a pony. Miniature horses are usually 34–38 inches tall, which puts them squarely in the pony category. However, miniature horses are considered by many enthusiasts to be a distinct breed of horse — like the Falabella, for instance — and one that keeps more of the horse body type and proportions."

The specifics that make miniature horses distinct from ponies are a bit controversial among horse enthusiasts. Many point out that miniature horses are ponies, since height is the primary distinguishing factor, and that the special title is more to do with increasing their popularity as pets. However, others say that miniature horses are specialized breeds with specific body type standards which sets them apart from ponies.

So whereas ponies have a stocky build — including shorter legs, longer bodies, a more barrel-like shape and thicker necks than horses — miniature horse enthusiasts breed their tiny steeds to have a body type similar in proportion to horses. The miniature horse below is a great example:

Black American miniature horse standing in the garden.Black American miniature horse standing in the garden. (Photo: Zuzule/Shutterstock)

Of course, the body type of miniature horses varies greatly depending on breeding and the different standards by the many registration associations. The main requirement for being considered a miniature horse is height.

They must be typically shorter than 38 inches as measured at the last hairs of the mane (not the withers). For instance, the American Miniature Horse Association states, "Horses registered with AMHA must meet the Association Standard of Perfection and cannot exceed 34 inches in height measured from the last hairs of the mane."

Whatever they're called, there is definitely a difference between miniature horses and full-sized horses:

Miniature horses are ponies, but they've been selectively bred to have a horse-like phenotype.Miniature horses are ponies, but they've been selectively bred to have a horse-like phenotype. (Photo: Edoma/Shutterstock)

The Falabella is perhaps the most famous breed of miniature horse. In 10 strange and beautiful horse breeds, we point out, "These tiny horses rarely stand taller than 32 inches at the withers. The breed originated in Argentina in the mid-1800s with Patrick Newtall and son-in-law Juan Falabella, and were first imported to the U.S. in 1962. They are sturdy and strong, thanks to the mix of Criollo, Welsh pony, Shetland pony and small Thoroughbred breeds that were added to the mix when the Falabella breed was being developed. They are used in show, and can be trained to pull carts and even be ridden by very small children."

Falabella miniature horses come in a wide range of colors, with bay and black being most common, but also come in pinto and palomino coloration, and even leopard-spotted such as with the mare grazing with her foal in this photo:

A Falabella mare and foal graze on meadow in summer.A Falabella mare and foal graze on meadow in summer. (Photo: Olga_Phoenix/Shutterstock)

Another breed of miniature horse is the South African Miniature Horse, developed starting around 1945 by Wynand de Wet. The breed gained recognition in 1989, and there are now around 700 miniature horses registered in South Africa.

Miniature horses can be quite athletic and are used in show, including pulling carts and jumping obstacles — though of course without a rider. And as mentioned, they also can make excellent companion animals and guide animals.

American Miniature Horse Registry writes, "Miniatures are well suited for everyone from the novice horse person to the consummate show professional. Their roles vary from backyard pet to fun parade entries to gorgeous show horses to therapy horses for persons with special needs or companions to the elderly. Whatever your interest in horses, it is likely there is a Miniature Horse suitable for the job!"

Miniature horses are the smallest of horse breeds. Miniature horses are the smallest of horses, but are just as active. (Photo: Vera Zinkova/Shutterstock)

Regardless of their purpose or use, and regardless of the controversy surrounding their name or breed standards, miniature horses are undeniably adorable. Combining this cuteness with their intelligence and disposition, it's no wonder they have seen such a surge in popularity over the last several decades.

A miniature horse rears up in display. A miniature horse rears up in display. (Photo: Alexia Khruscheva/Shutterstock)

Mini horse foals are amazingly petite. Mini horse foals are amazingly petite. (Photo: Geoffrey Kuchera/Shutterstock)

A herd of Falabella miniature horses run on meadow in summer.A herd of Falabella miniature horses run on meadow in summer. (Photo: Olga_Phoenix/Shutterstock)

A Falabella foal. A Falabella foal. (Photo: DragoNika/Shutterstock)

A miniature horse stands regally on a hillside. A miniature horse stands regally on a hillside. (Photo: Anastasia Vetkovskaya/Shutterstock)

It's no wonder why miniature horses have become so popular as pets. It's no wonder miniature horses have become so popular as pets. (Photo: DragoNika/Shutterstock)

Miniature horses are silhouetted on a hillside.Miniature horses are silhouetted on a hillside. (Photo: Julia Remezovas/Shutterstock)

Jaymi Heimbuch ( @jaymiheimbuch ) focuses on wildlife conservation and animal news from her home base in San Francisco.