1Average Quarter Horse (BCS 5)
Inputs
Result
Weight = 72² × 64 / 330 = 331,776 / 330 = 1,005 lbs. At BCS 5, this horse needs 1.5–2.0% BW in forage = 15.1–20.1 lbs/day of hay, with minimal or no grain.
Estimated Weight
1,005 lbs
Metric
456 kg
BCS
5/9
Measure around the barrel behind the elbow and over the withers
Point of shoulder to point of buttock (straight line)
Inputs
Result
Weight = 72² × 64 / 330 = 331,776 / 330 = 1,005 lbs. At BCS 5, this horse needs 1.5–2.0% BW in forage = 15.1–20.1 lbs/day of hay, with minimal or no grain.
Inputs
Result
Pony formula: 60² × 48 / 299.2 = 172,800 / 299.2 = 578 lbs. At BCS 7, restrict to 1.5% BW forage (8.7 lbs/day) with no grain. Increase exercise to promote weight loss.
Inputs
Result
Draft formula: 86² × 76 / 310 = 562,256 / 310 = 1,814 lbs. Draft horses use divisor 310 instead of 330 to account for larger barrel circumference. Daily forage: 27–36 lbs of hay.
The most accurate field method uses two tape measurements: heart girth (around the barrel behind the elbow) and body length (point of shoulder to point of buttock). The Carroll & Huntington formula multiplies girth squared by length, then divides by 330 for standard horses.
| Girth (in) | Length (in) | Est. Weight (lbs) |
|---|---|---|
| 60" | 55" | 600 lbs |
| 72" | 64" | 1,005 lbs |
| 78" | 68" | 1,254 lbs |
| 85" | 72" | 1,576 lbs |
The Henneke scale rates horses from 1 (emaciated) to 9 (extremely fat) by evaluating fat deposits at six body areas: neck, withers, behind the shoulder, ribs, loin, and tailhead. A score of 5 is considered ideal for most horses.
| BCS | Condition | Rib Visibility |
|---|---|---|
| 1–2 | Emaciated/Very Thin | Easily visible |
| 3–4 | Thin/Moderately Thin | Faintly visible |
| 5–6 | Ideal/Moderately Fleshy | Felt, not seen |
| 7–9 | Overweight to Obese | Difficult to feel |
Most horses need 1.5–2.0% of their body weight in forage (hay or pasture) daily. A 1,000-pound horse at BCS 5 needs 15–20 lbs of hay per day. Never drop below 1.0% body weight in forage, as this increases risk of colic and gastric ulcers.
| Horse Weight | Min Forage | Ideal Forage | Weight Loss |
|---|---|---|---|
| 800 lbs | 8 lbs/day | 12–16 lbs/day | 8–12 lbs/day |
| 1,000 lbs | 10 lbs/day | 15–20 lbs/day | 10–15 lbs/day |
| 1,200 lbs | 12 lbs/day | 18–24 lbs/day | 12–18 lbs/day |
| 1,500 lbs | 15 lbs/day | 22–30 lbs/day | 15–22 lbs/day |
Quarter Horses typically weigh 1,000–1,300 lbs at a healthy BCS of 5–6. Smaller stock-type Quarter Horses may be closer to 1,000 lbs while halter-type animals can exceed 1,300 lbs. Use heart girth and body length measurements for an individual estimate.
| Breed | Height | Weight Range |
|---|---|---|
| Arabian | 14.1–15.1 hh | 800–1,000 lbs |
| Quarter Horse | 14.2–16 hh | 1,000–1,300 lbs |
| Thoroughbred | 15.2–17 hh | 1,000–1,200 lbs |
| Clydesdale | 16.2–18 hh | 1,600–2,200 lbs |
The Carroll & Huntington formula (Girth² × Length / 330) is accurate to within ±3–5% for horses at BCS 4–6. It tends to underestimate very heavy horses and overestimate very thin ones. For ponies, a divisor of 299.2 improves accuracy due to their stockier proportions.
| Horse Type | Formula Divisor | Accuracy |
|---|---|---|
| Light / Riding | 330 | ±3–5% |
| Pony | 299.2 | ±4–6% |
| Draft / Heavy | 310 | ±4–7% |
| Miniature | 299.2 | ±5–8% |
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Last Updated: Mar 9, 2026
This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.