How to use the hay needs calculator
- Enter the number of animals and the weight of each animal in pounds.
- Enter the share of body weight you plan to give per day as hay. The box starts with an example value that you can change.
- Enter the days to cover. Optionally add a waste allowance and the weight of one bale.
- Read the hay needed per animal per day, for all animals per day, for the whole period, in tons and in bales.
Formula
Per animal per day = body weight x share of body weight / 100
Total = per animal per day x animals x days x (1 + waste % / 100)
Tons = total pounds / 2,000 Bales = total pounds / bale weight, rounded up
The share of body weight is an input, not a recommendation. A ton is 2,000 pounds.
One 1,000 pound animal at 2% a day for 30 days
At 2% of body weight, one 1,000 pound animal gets 1,000 x 0.02 = 20 pounds a day. Over 30 days that is 600 pounds, or 0.3 tons.
For two 1,200 pound animals at 2.5% for 14 days with a 10% waste allowance, each gets 30 pounds a day, so 60 pounds a day for both. The total is 60 x 14 x 1.10 = 924 pounds, which is 0.462 tons. With 50 pound bales, 924 / 50 = 18.48, so you would buy 19 bales.
A calculator, not a feeding plan
This page does arithmetic on the percent you choose. It does not know your animals, their age, work, condition, pasture or the quality of the hay, and it makes no claim about how much any animal should eat. Ask a veterinarian or your local extension service how much to feed, then enter that figure here to plan how much to buy.
The 2% starting value is only an example so the tool shows a result when you open it. Replace it with the number you were given.
Planning a purchase
Buying hay by the bale means rounding up to whole bales, and bale weights vary, so weigh a few if you can. A waste allowance covers hay that is dropped or spoiled. Storage space is another practical limit, and the tons figure helps you compare against what you can keep dry.
To plan costs, the annual pet cost calculator adds up regular spending, and the unit converter changes pounds to kilograms. For the space a flock needs, try the chicken coop size calculator.
Assumptions and limits
- The percent of body weight is an example you can change and is not a feeding recommendation.
- All animals weigh the same and eat the same share.
- Bale weights are the figure you enter. Real bales vary.
- Nutrition, pasture, grain and the quality of the hay are not modeled.
Frequently asked questions
How much hay does a 1,000 pound horse eat in a day?
That depends on the animal and the advice of your veterinarian. At the example 2% of body weight, the arithmetic gives 20 pounds a day, but the tool does not recommend a percent.
How do I work out hay for a month?
Multiply the daily amount per animal by the number of animals and the days. At 20 pounds a day for 1 animal, 30 days needs 600 pounds.
How many bales do I need?
Divide the total pounds by the weight of one bale and round up. Enter the bale weight and the tool does it for you.
Why add a waste allowance?
Some hay is dropped, trampled or spoils. Adding a percent gives you a margin so that you do not run short.