How Much Hay Do I Need?
Daily hay per animal and the total to stock for winter, worked out the way agricultural extension services do it: bodyweight, dry matter, then a waste allowance.
Starting value is a typical goat, not a sourced figure.
Published range for goats: 2–6%. Starts at 3.75%.
182 days is a six-month winter. Waste runs 10–50% depending on how hay is fed; 20% is a starting choice within that range.
Bales vary a lot by size and supplier, so weigh one or ask yours.
Hay for 182 days, all 2 together
2.1 kg each a day · 4.2 kg a day in total · includes 20% waste
Worked out as bodyweight × 3.75% dry matter, then ÷ 0.9 because hay is about 90% dry matter, then plus waste — the method Washington State University Extension sets out. It assumes hay is the whole forage diet for those days; pasture or concentrate feed reduces it.
WSU Extension gives goats a wide 2–6% of bodyweight a day in dry matter. 3.75% is this site's feed planning figure; a goat also getting concentrate will eat less hay.
Sources checked: October 2026.
How the hay amount is worked out
The calculator follows the method Washington State University Extension sets out for winter hay. Daily dry matter is bodyweight multiplied by an intake percentage. Hay is about 90% dry matter, so that figure is divided by 0.9 to give the weight of hay itself. The daily total is then multiplied by the number of days on hay, with a waste allowance added on top.
The starting intake for each species is the planning figure this site's feed calculator already uses: 3.75% of bodyweight for goats, 3% for sheep and 2% for horses. Each sits inside the range WSU Extension publishes (goats 2–6%, sheep 2–5%, horses 1.5–3%), and you can change it within that range.
WSU Extension puts hay waste at 10–50% depending on how it's fed. The 20% starting allowance is a choice within that range, so change it to suit how you feed hay. Rabbits don't have a weight-based figure: the RSPCA advises a bundle of hay as big as the rabbit every day, with hay available at all times.
Common questions
- How much hay does a goat need for winter?
- A 50 kg goat at 3.75% of bodyweight eats about 1.9 kg of dry matter a day, which is about 2.1 kg of hay. Over a 182-day winter that's roughly 380 kg per goat, or about 455 kg with a 20% waste allowance.
- How much hay does a horse eat a day?
- About 2% of bodyweight in dry matter as a planning figure, so a 500 kg horse needs about 11 kg of hay a day. University of Nebraska Extension puts free-choice hay or pasture intake at 2–2.5% of bodyweight in dry matter.
- How many bales of hay do I need?
- Enter the weight of one of your bales and the calculator divides the season total by it. Bale weights vary too much by size and supplier to assume a standard one, so weigh a bale or ask your supplier.
- Does the calculator include pasture or hard feed?
- No. It assumes hay is the whole forage diet for the days you enter. Grazing or concentrate feed reduces how much hay you need.
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