How to Measure Your Horse's Weight Accurately

Accurately knowing your horse's weight is crucial for administering medications, de-worming, and monitoring overall health.

Livestock Scale

The most accurate method for measuring a horse's weight is with a livestock scale. Many veterinary clinics and auction barns have these scales available. You may be able to weigh your horse by visiting these locations.

Truck Scale

You can weigh a horse on a truck scale by loading the horse onto a trailer and weighing the entire rig, both with and without the horse. The horse's weight is the difference. Variations like gear and fuel levels can affect accuracy, as truck scales may be off by 20 to 40 lbs. This method can be complex and time-consuming.

Measuring Your Horses Body

If you can’t get your horse on a livestock scale, you can approximate its weight by measuring its body. An approximate weight can be measured with a special weight tape. Weight tapes are available at tack shops and feed stores. They are inexpensive and easy to use. They aren’t completely accurate, because they only measure around the girth of the horse, and don’t take into consideration other things like fat/muscle ratio, height, body type, and overall condition.

Ensure your horse is tied safely and standing quietly. With a purchased weight tape, measure around the horse so the tape goes around the girth area, and up over the horse, just behind withers. Take the measurement where the end of the tape meets the scale on the tape. If you are tracking your horse’s weight, you’ll need to be careful that you place the tape in exactly the same place each time, and hold it with the same tension. If you have a pony or foal, a regular tape made for mature horses may not be accurate. Weight tapes for specific body types can be purchased.

Weight Chart

A regular tape measure or a piece of twine can substitute for a weight tape. Use the weight chart from OMAFRA to estimate your horse's weight.

To further estimate weight, measure around the horse as previously described, and add a measurement from the shoulder to the haunch. Then calculate: (girth x girth x body length) 300 = Horse's weight. This method requires multiplying the girth measurement twice, sometimes referred to as heart-girth. For example, a horse measuring 76 inches around and 38 inches long would weigh approximately 782 lbs.

Estimating Weight

The girth x girth x body length ÷ 300 = Horse’s weight method is the traditional formula for estimating weight, but other formulas do exist. A Better "Weigh" for Horses: Equine Weight Estimation looks at the accuracy of common formulas and presents a slightly different way of measuring and calculating the weight.

This calculation will not be as accurate for ponies and foals. Here is a formula to calculate foal weight. To estimate a miniature horse’s weight, this calculating bodyweight of minis formula can be used.

Remember, all methods except the livestock scale provide estimates. These are generally sufficient for planning feed, medications, and supplements. If you require precise weight details, consult your veterinarian for the most accurate approach.