How to Measure a Horse's Weight

Have your horse 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

You don’t need a special weight tape to get an approximate weight, however. You can use a regular tape measure or a piece of twine which you measure. This weight chart on the OMAFRA site can then be used to determine an approximate weight.

Another way to find an approximate weight is to measure around the horse as described and take an additional measurement from the point of the horse’s shoulder to the ‘edge’ of the haunch. With this measurement you can then do a bit of math: girth x girth x body length ÷ 300 = Horse’s weight. Yes, you multiply the measurement around the girth twice. You may also see this referred to as heart-girth. So if your horse is 76 inches around and 38 inches long you would calculate 76 x 76 x 38 ÷ 300 = 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.

It’s important to remember that all of these methods, except the livestock scale, will be estimations. These estimations should be sufficient for calculating feed, medications, and supplements. If however, you need a very accurate weight, consult with your veterinarian for the best approach.