Horse weight calculator
Measure your horse's heart girth and body length with a soft tape, and get an estimated weight in kilograms, pounds and stone. Works in centimetres or inches.
Calculate your horse's weight
Likely range 432 to 488 kg (about plus or minus 6%).
This measurement is outside the typical range the formula was built on. Treat the estimate as rough, and use a livestock scale if one is available.
As a general guide, most horses eat about 7 to 9 kg of forage a day (1.5 to 2% of bodyweight).
General guidance, not veterinary advice. An estimate from a tape is not a substitute for a livestock scale, and should never be used on its own to work out medication doses.
How to measure your horse
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Stand square on level ground
Hold the head up and level, with all four feet under the horse. A horse leaning or standing on a slope will throw the numbers off.
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Measure the heart girth
Pass a soft tape around the barrel, just behind the elbows and over the highest point behind the withers. Keep it flat and level on both sides, pull it snug without squeezing, and read it at the end of a breath out.
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Measure the body length
In a straight line from the point of the shoulder (the front of the shoulder joint) to the point of the buttock (the bony point at the back of the hindquarters).
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Repeat it the same way each time
Use the same tape, the same time of day and the same method. A consistent reading tells you far more about change than any single number.
How the estimate works
Weight in kilograms equals heart girth in centimetres, squared, multiplied by body length in centimetres, then divided by a number that depends on body type. The standard divisor of 11,900 comes from published work by Carroll and Huntington (1988).
| Body type | Divisor |
|---|---|
| Standard | 11,900 |
| Pony | 11,000 |
| Draft / Cob | 12,600 |
| Narrow-bodied | 12,200 |
Only the standard divisor comes from the published formula. The other body types are approximate adjustments, so treat them as a guide. Typical accuracy is about plus or minus 6%.
Questions owners ask
How accurate is a horse weight calculator?
Estimates from heart girth and body length are typically within about 6% of the true weight for most horses. That makes them good for spotting change over time. A livestock scale or weighbridge is more accurate when you need a precise figure, and you should never use an estimate alone to work out medication doses. Ask your vet.
How do I measure heart girth and body length?
Stand your horse square on level ground with the head up. For heart girth, pass a soft tape around the barrel just behind the elbows and over the highest point behind the withers, snug but not tight, and read it at the end of a breath out. For body length, measure in a straight line from the point of the shoulder to the point of the buttock.
How often should I weigh my horse?
Many owners check every two to four weeks, and more often while managing weight. Measure at the same time of day, with the same tape and the same method, so the changes you see are real.
How much should my horse weigh?
There is no single right weight. It depends on height, build and breed, so judge weight together with body condition score and your vet's advice rather than aiming for a number.
What is the difference between weight and body condition score?
Weight tells you how heavy your horse is. Body condition score tells you how much fat they are carrying, using a 1 to 9 scale assessed across six areas of the body. Two horses can weigh the same and be in very different condition, so it helps to track both.
Why does the calculator warn about my measurements?
The formula is built on heart girths between about 100 and 200 cm (39 to 79 inches). Outside that range the estimate is still shown, but it is rougher, so use a livestock scale if you can.
Is the information I enter saved?
No. Everything is calculated in your browser. Nothing you type is sent anywhere or stored.
Track it over time, and feed to it.
Equus Metric saves every measurement, scores body condition region by region, and builds a daily ration around your horse. Try it free for 14 days, then £9.99 a month.
Coming soon to the App Store.