Hay Bale Feed Duration Calculator
Calculate how long a hay supply lasts from horse count, bale weight, and daily feeding rate.
Returns days remaining, monthly cost, and annual tonnage needed.
How much hay does a horse need?
Horses are hindgut fermenters and require a forage-based diet. The general rule is that a horse should eat 1.5–2.5% of its body weight in forage per day, with most of that being hay when pasture is unavailable.
Daily hay consumption formula:
Daily hay (lbs) = Horse weight (lbs) × feed rate (%)
| Horse Type | Weight (lbs) | Feed Rate | Daily Hay (lbs) |
|---|---|---|---|
| Miniature horse | 200–350 | 2.0% | 4–7 |
| Light riding (Arab, QH) | 900–1,100 | 1.5–2.0% | 14–22 |
| Warmblood / Sport horse | 1,200–1,400 | 1.5–2.0% | 18–28 |
| Draft horse | 1,600–2,200 | 1.5–2.0% | 24–44 |
| Broodmare (late gestation) | 1,100 | 2.0–2.5% | 22–28 |
| Growing yearling | 700 | 2.0–2.5% | 14–18 |
Hay bale sizes:
| Bale Type | Weight Range | Average Weight | Flakes per Bale |
|---|---|---|---|
| Small square (2-string) | 40–60 lbs | 50 lbs | 10–12 |
| Small square (3-string) | 100–140 lbs | 120 lbs | 16–20 |
| Large round | 800–1,500 lbs | 1,000 lbs | N/A |
| Large square (3×3×8) | 800–1,200 lbs | 1,000 lbs | N/A |
| Large square (4×4×8) | 1,500–2,000 lbs | 1,800 lbs | N/A |
Waste factor:
Not all hay gets eaten. Ground feeding wastes 15–30%. Hay nets reduce waste to 5–10%. Hay racks waste about 10–15%.
Worked example:
3 horses averaging 1,100 lbs each, fed at 2% body weight, using small square bales (~50 lbs):
- Daily hay per horse: 1,100 × 0.02 = 22 lbs
- Daily total: 22 × 3 = 66 lbs
- With 15% waste: 66 × 1.15 = 75.9 lbs/day
- Bales per day: 75.9 ÷ 50 = ~1.5 bales/day
- 100 bales will last: 100 × 50 ÷ 75.9 = ~66 days
Seasonal planning:
In many regions, hay season is June–September. Winter feeding (no pasture) runs 5–7 months. For 3 horses through a 6-month winter:
- 75.9 lbs/day × 180 days = 13,662 lbs
- At 50 lbs/bale = 274 small square bales (or about 14 large round bales)
Storage: Properly stored hay (under cover, off the ground, good ventilation) retains nutritional value for 1–2 years. Wet or moldy hay can cause colic and respiratory issues — never feed it.