Horses • weight-growthVerified Scientific Formula
Horse Weight Calculator (Heart Girth & Length)
Calculates horse body weight in pounds or kilograms from heart girth and body length measurements.
Enter Parameters
Calculated Output
Estimated Horse Body Weight
965lbs438 kg
Estimated Expected Range: 926 – 1,004 lbs
What This Result Means
Based on a 70 in girth and 65 in length, estimated weight is ~965 lbs.
Calculation Details & Practical Equivalents
Daily Forage Need (2% BW baseline)
19.3 lbs/day
Daily Water Intake Baseline
12 gallons/day
Maintenance Digestible Energy (DE)
16 Mcal/day
Formula & Mathematical Methodology
Standard Mathematical Formula
Weight (lbs) = [Heart Girth (in)]² × [Body Length (in)] ÷ 330 | Weight (kg) = [Girth (cm)]² × [Length (cm)] ÷ 11880
Formula Variables Defined
GirthHeart Girth(inches (or cm))
Circumference directly behind front legs and over withers
LengthBody Length(inches (or cm))
From point of shoulder to point of buttock
Step-by-Step Calculation Example
Example: 72 in Heart Girth, 66 in Body Length
An adult light horse with a 72-inch heart girth and 66-inch body length.
- 72 × 72 = 5,184
- 5,184 × 66 = 342,144
- 342,144 ÷ 330 = 1,036.8 lbs (~470 kg)
Final Output: 1,037 lbs (470 kg)
Key Assumptions
- Horse is standing squarely on level ground.
Biological Limitations
- Draft breeds use ~301-310 denominator.
Verified Scientific & Veterinary Sources
Version: 1.0•Methodology Reviewed: 2026-01-22
1. Nutrient Requirements of Horses (Sixth Revised Edition)textbook
National Research Council (NRC) Committee on Nutrient Requirements of Horses (2007). National Academies Press, Washington, D.C.
Access Source Authority 2. Relationship between condition score, physical measurements and body fat percentage in marespeer-reviewed
Henneke, D.R., Potter, G.D., Kreider, J.L., and Yeates, B.F. (1983). Equine Veterinary Journal, 15(4), 371-372
Horse Weight Calculator (Heart Girth & Length) — FAQs
From point of shoulder straight along the side to the point of the buttock (tuber ischii).
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