# How much to feed a horse: forage, grain and water > How much hay a horse needs each day as a share of body weight, how to turn that into flakes, when grain is needed, how much water to expect, and how to change feed safely. Canonical: https://lucernel.com/guides/horse-feeding-guide Last updated: 2026-10-07 Type: Guide. Publisher: Lucernel. ## Short answer Forage comes first. The Merck Veterinary Manual says horses should get at least 1.5 to 2% of their body weight in forage per day on a dry-matter basis, so a 1,000-pound horse needs about 15 to 20 pounds of hay or its equivalent. Weigh the hay, because a flake can weigh 5 pounds in one bale and 7 in another. Add grain only when forage alone does not meet the horse’s needs, keep water in front of the horse, and change feed slowly. - **Choose this if:** A notebook and a scale are enough for one easy-keeping horse on a steady diet. - **Choose the other option if:** Trotley helps when you want weight, feed events and care dates for each horse in one record, for one horse or a small stable. ## Side by side | | Notebook and scale | Trotley | | --- | --- | --- | | Records feed events | Yes | Yes, as an event type for each horse | | Weight history for each horse | Partly, a list of numbers | Yes, with charts over time | | Reminders for farrier, dental, vaccines and medication | No | Yes | | Several horses in one place | Partly | Yes, with a stable calendar | | Report for the vet or a new owner | Partly, the notebook itself | Yes, PDF or CSV | | Works offline | Yes | Yes | | Calculates a ration for you | No | No, you enter what you feed | ## Forage first: how much hay The Merck Veterinary Manual gives the current recommendation: horses should receive at least 1.5 to 2% of their body weight in forage per day on a dry-matter basis. Forage can be pasture, hay, haylage or substitutes such as hay cubes and hay pellets. Penn State Extension puts it at at least about 2% of body weight. The average maximum daily intake is usually 2 to 2.5% of body weight, according to Merck, with ponies and weanlings sometimes going higher. Dry matter means the feed with the water removed, so hay as fed weighs a little more than these figures. These are starting points, and your vet or an equine nutritionist can set a number for your horse. ## How to turn it into flakes You need the horse’s weight, and a weight tape or a scale is better than a guess. Multiply it by 0.015 and 0.02 to get a daily range in pounds. For a 1,000-pound horse that is 15 to 20 pounds. Then weigh a flake. Penn State Extension notes that flake weight varies with how tightly the bale was packed: one cutting might give 5-pound flakes and another 7-pound flakes, so 5 flakes a day is about 25 pounds in one case and 35 in the other. Within one bale, flakes also differ. For our 1,000-pound horse at 20 pounds, that is about 4 flakes of 5 pounds or about 3 flakes of 7. To weigh hay, Penn State suggests a trash can on a bathroom scale, taring the empty can, or a hay net on a luggage scale. ## Water Merck puts the average minimum daily water need of a sedentary adult horse in mild weather at 5 liters per 100 kilograms of body weight. A 500-kilogram horse (about 1,100 pounds) in minimal work typically drinks 21 to 29 liters a day, or roughly 5.5 to 7.7 US gallons, on a mixed hay and grain ration or pasture. If it eats only dry hay, its intake can almost double. Hot weather, heavy work, sweating and lactation raise the need. Merck recommends unlimited free access to clean water and warns that too little water reduces feed intake and raises the risk of impaction colic. ## When grain is needed Penn State Extension says forage should be the foundation of every horse’s diet. Concentrates such as grain, sweet feed and pellets are added to make up for what forage lacks. Working, growing and pregnant or lactating horses typically need more energy or protein than hay or pasture can offer alone. Many easy keepers need no grain, only a vitamin and mineral supplement or a ration balancer. Penn State’s rule is about 2% of body weight in total feed daily, with at least half of it forage. Measure grain by weight, not by scoop. Penn State shows that three types of feed in the same 3-quart scoop weighed 1 pound 6 ounces, 2 pounds 7 ounces and 1 pound 15 ounces. Re-weigh the scoop whenever you change feed, and follow the feed tag for your horse’s weight and workload. ## Changing feed slowly Penn State Extension explains that the microbes in a horse’s gut adjust to what it eats, and a sudden change does not give them time. It can cause colic or diarrhea. It recommends changing to new feed over a few weeks. The same applies to moving from hay to spring pasture, which can be high in sugars and starch that trouble horses prone to laminitis, insulin dysregulation or Cushing’s disease. ## Signs of too little or too much Merck suggests adjusting the amount fed to keep a body condition score between 4 and 6 on the 9-point Henneke scale. A score of 7 or more is overweight and 8 to 9 is obese. Thin horses tolerate cold and stress poorly and are more prone to infections. Obese horses have more risk of laminitis, colic from lipomas, insulin resistance and joint stress. For a horse that needs to lose weight, Penn State recommends limiting hay to about 1% of body weight and feeding a ration balancer instead of grain. For a thin horse, ask your vet to look for a cause first, such as dental or other health problems, and change the ration slowly. Call your vet if a horse is losing weight, is very thin, stops eating or gets colic or diarrhea after a feed change. Merck lists emaciated and very thin horses (scores 1 and 2) as at risk of refeeding problems, so a starved horse needs veterinary guidance before its feed is increased. Disclosure: Trotley is made by Lucernel, the publisher of this article. ## Frequently asked questions ### How much hay should a horse eat per day? At least 1.5 to 2% of body weight in forage on a dry-matter basis, according to Merck. For a 1,000-pound horse, that is about 15 to 20 pounds. ### How many flakes is that? It depends on the flake. Penn State found flakes of about 5 pounds in one cutting and 7 in another, so weigh a few from your own bale. ### How much water does a horse drink? A 500-kilogram horse in minimal work typically drinks 21 to 29 liters a day, and nearly twice that on dry hay alone, per Merck. Provide free access to clean water. ### Does every horse need grain? No. Many easy keepers do well on forage plus a ration balancer or supplement. Penn State says working, growing, and pregnant or lactating horses typically need more than forage alone. ### Is Trotley available? See the official app page for current availability and pricing. ## Our pick: Trotley, the stable ledger for your horses Trotley keeps each horse’s weight history, feed, farrier, dental, vaccination and medication events in one record, with reminders for what is due. It does not work out a ration for you, so use your vet or a nutritionist for the numbers and Trotley to keep track of what you feed and how the horse responds. - Weight history charts for every horse - Feed, farrier, dental, vaccine and medication events - PDF reports and CSV export for the vet or a new owner [See how Trotley works](https://lucernel.com/apps/trotley) ## Sources (checked 2026-10-01) - [Merck Veterinary Manual: Nutritional requirements of horses and other equids](https://www.merckvetmanual.com/management-and-nutrition/nutrition-horses/nutritional-requirements-of-horses-and-other-equids) - [Penn State Extension: The importance of weighing horse feed](https://extension.psu.edu/the-importance-of-weighing-horse-feed) - [Penn State Extension: The scoop on grains and concentrates](https://extension.psu.edu/the-scoop-on-grains-and-concentrates) - [Penn State Extension: Transitioning horses to spring grazing](https://extension.psu.edu/transitioning-horses-to-spring-grazing)