Horse Weight Estimator
Estimate your horse's weight using a simple tape measure — no weighbridge needed. Uses the standard heart girth and body length formula used by vets and equine nutritionists.
Horse Weight Guide
The Leighton Hardman Formula
The standard formula for estimating horse weight: Weight (kg) = (Heart girth cm² × Body length cm) ÷ 11,877. Heart girth is measured around the barrel just behind the elbow and withers. Body length is measured from the point of shoulder to the point of buttock. This formula has an accuracy of approximately ±10% compared to weighbridge measurements. A weigh tape (marked in kg rather than cm) provides a quicker but less accurate alternative.
Why Weight Matters
Accurate weight is essential for: worming (dose must be based on weight — under-dosing allows resistance to develop), feeding rations (most feed companies provide amounts per 100kg bodyweight), medication dosing (all equine medications are weight-based), monitoring health trends (weight loss or gain can be an early indicator of health issues), and insurance and competition purposes. Many horses are significantly overestimated by owners — a 2019 World Horse Welfare survey found 85% of owners unde
Body Condition Scoring
Weight alone doesn't tell the full picture — body condition score (BCS) assesses fat coverage. The Henneke scale (1–9): 1 = emaciated, 5 = ideal, 9 = extremely obese. Most performance horses should be kept at 4–5, breeding stock at 5–6. Key areas to assess: ribs (should be felt but not seen), crest (should not be firm or cresty), hindquarters and spine (fat deposits around the tail head indicate overweight). Ponies, native breeds, and certain horse breeds (Andalusian, Warmblood) have a genetic t
Weight Management in Horses
Overweight horses have significantly elevated risk of laminitis — particularly dangerous in ponies, native breeds, and easy keepers. Restricting grass access (strip grazing, grazing muzzle, stable time) is more effective than reducing hay. Never starve a horse to reduce weight — this risks hyperlipemia (fatal in ponies and donkeys). A weight loss target of 0.5–1% of bodyweight per week is safe. Underweight horses need increased quality forage before adding concentrates — calories from hay are mo
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