Forage planning formula
The University of Minnesota range is stated for total feed, including forage plus grains, and says most horses should receive at least 75% of daily feed as forage. HayRatio uses it as a transparent planning starting point—not proof that the output equals an individual horse’s actual hay requirement.
Versioned references
- University of Minnesota Extension
Ten ways to stretch your horse's hay supplyReviewed 2024The 1.5%–2.5% total-feed planning range, a common 2% target, bale-weight examples, and observed hay-waste ranges.
- Penn State Extension
The Importance of Weighing Horse FeedUpdated August 14, 2026Why hay and flakes should be weighed instead of estimated by volume, plus the roughly 2% body-weight example.
- American Association of Equine Practitioners
Care Guidelines for Equine Rescue and Retirement FacilitiesFourth edition, 2019; PDF available 2024Broad forage-based maintenance guidance and professional referral for individual or special needs.
- Penn State Extension
Buying Winter Hay for HorsesRetrieved August 31, 2026A 1,100-pound × 2% = 22-pound worked example and the reminder that other feed changes hay needs.
- University of Minnesota Extension
Estimating actual and ideal bodyweight of adult horsesReviewed 2024Research-derived adult-horse bodyweight equations by horse type and definitions for girth, length, height, and neck measurements.
Adult weight estimator
The measurement estimator reproduces the horse-type equations in the reviewed University of Minnesota source. Inputs are girth, body length, height, and neck circumference; output is an estimated actual scale weight. The supported population is adult, non-pregnant horses. It does not estimate ideal weight or body condition.
Validation limits
| Horse weight | 100–3,000 lb or kg equivalent |
|---|---|
| User-selected percentage | 1.5%–2.5% |
| Bale weight | Greater than 0; no more than 2,500 lb or kg equivalent |
| Planning days | 1–366 whole days |
| Waste | 0%–75% |
| Bale price | 0–100,000 in the user’s currency |
Safety and scope
Results are educational forage planning ranges. HayRatio does not prescribe grain, concentrates, supplements, salt, water, or medications; balance nutrients; or provide condition-specific advice. It is out of scope for foals, growing horses, pregnant or lactating mares, acute illness, recovery, or special-health diets. Confirm feeding changes with a veterinarian or qualified equine nutritionist.