Horse Weight Calculator
Estimate horse or pony weight from heart girth and body length.
Enter your values
Enter the heart girth in cm.
Choose one of: Adult horse, Pony, Yearling, Weanling, Draft horse.
Enter the body length (point of shoulder to point of buttock) in cm.
Enter the daily feed as % of bodyweight in %.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Estimated weight
- 461 kg
- In pounds
- 1,016 lb
- Daily forage and feed
- 9.2 kg dry matter
- Minimum forage (1.5%)
- 6.9 kg
- Wormer dose basis
- 461 kg — round up to the nearest marked weight
- Rider weight guide (20%)
- 92 kg including tack
Working
- 1185^2 x 160 / 11,877 = 461 kg
Quick answer
Horse weight is estimated from heart girth squared times body length divided by a breed constant, a method within about 5% of a weighbridge.
kg = girth cm^2 x length cm / 11877
At a glance
| What it does | Estimate horse or pony weight from heart girth and body length. |
|---|---|
| Category | Pets |
| Inputs needed | Heart girth, Type, Body length (point of shoulder to point of buttock), Daily feed as % of bodyweight |
| Main output | Estimated weight |
| Formula | kg = girth cm^2 x length cm / 11877 |
| Cost | Free — no sign-up, no download |
How to use the Horse Weight Calculator
- 1Measure heart girth with a tape right behind the withers and elbows, at the end of an exhale.
- 2Measure body length from the point of the shoulder to the point of the buttock.
- 3Pick the type so the right constant is used, then use the weight for feed and wormer dosing.
Inputs explained
- Heart girth(cm)
- Enter the heart girth in cm.
- Type
- Choose one of: Adult horse, Pony, Yearling, Weanling, Draft horse.
- Body length (point of shoulder to point of buttock)(cm)
- Enter the body length (point of shoulder to point of buttock) in cm.
- Daily feed as % of bodyweight(%)
- Enter the daily feed as % of bodyweight in %.
Worked example
Using the values the calculator loads with:
Inputs
- Heart girth185 cm
- TypeAdult horse
- Body length (point of shoulder to point of buttock)160 cm
- Daily feed as % of bodyweight2 %
Results
- Estimated weight461 kg
- In pounds1,016 lb
- Daily forage and feed9.2 kg dry matter
- Minimum forage (1.5%)6.9 kg
- Wormer dose basis461 kg — round up to the nearest marked weight
- Rider weight guide (20%)92 kg including tack
- 185^2 x 160 / 11,877 = 461 kg
Frequently asked questions
How accurate is a tape estimate?
Within about 5% of a weighbridge for typical adult horses. Very fit, very fat or unusually shaped horses drift further from the formula.
Should I use this for medication dosing?
For wormers, yes, rounding up. For prescription medicines always confirm with your vet, who may want a weighbridge figure.
What do I need to enter into the Horse Weight Calculator?
Just 4 values: heart girth, type, body length (point of shoulder to point of buttock), daily feed as % of bodyweight. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Horse Weight Calculator work out the answer?
Horse weight is estimated from heart girth squared times body length divided by a breed constant, a method within about 5% of a weighbridge. It applies the formula kg = girth cm^2 x length cm / 11877 and shows the working so you can check each step by hand.
Is the Horse Weight Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.