How many acres per horse do you need?

Extension sources give different figures because they assume different management. Iowa State puts a mature horse on 1 to 2 acres of excellent, dense pasture, 2 to 2.5 acres of average pasture, and 3 or more acres of thin, unmanaged pasture. Penn State quotes 2 to 4 acres per 1,000 pound horse. About 2 acres is a fair starting point; your own figure depends on forage yield and grazing management.

How much grass does a horse eat per day?

Extension guidance puts a horse's daily hay intake at about 2 percent of bodyweight, and Iowa State treats 3 percent as a maximum. For a 1,000 pound horse that is about 20 pounds a day, which is far more forage than most people picture. This calculator uses the same 2 percent as a working figure for grazing.

Does rotational grazing reduce the acreage needed?

It can. Penn State describes rotational grazing as the system that yields the highest returns on available forage, because animals that stay on one field keep grazing their favorite plants while trampling and fouling the rest. How much land it saves is not a published constant. This calculator assumes 35 percent of forage is eaten under continuous grazing and 65 percent under rotation, which are its own working assumptions, and lets you switch between them.

Do I still need a dry lot if I have enough pasture?

Yes. A dry lot or sacrifice area lets you keep horses off wet ground, rest paddocks so they can regrow, and restrict grazing for horses prone to laminitis. Pasture acreage calculations assume the pasture gets rested, which is only possible if the horses have somewhere else to stand.

Horse property planning / Pasture

Horse Pasture Calculator: How Many Acres Per Horse

Everyone quotes two acres a horse. The real number depends on what your ground grows and how much of it reaches a horse rather than being trampled. Work it out from both.

Step 01

Set the herd

Live estimate

Horses

Bodyweight (lb)

Daily intake (of bodyweight) 2.0%

Extension guidance centers on 2% of bodyweight a day, with Iowa State treating 3% as a maximum.

Grazing season 180 days

Days a year the pasture actually feeds the horses. Hay covers the rest.

Forage yield

Low2,000 lb dry matter per acre Average3,500 lb dry matter per acre High5,000 lb dry matter per acre

Reasonable stand on decent soil.

Grazing management

Continuous grazingOne field, all season Rotational grazingPaddocks rested in turn

Horses on one field all season. Much of the growth is wasted.

Step 02

Calculated live

Pasture needed

Total acres — acres of grazing

Per horse: — acres
Daily intake: — lb dry matter per horse
Season requirement: — lb dry matter (whole herd)
Usable forage: — lb per acre (after waste)

Assumes 2.0% of bodyweight per day as dry matter.

You still need a dry lot.

Every acreage figure on this page assumes the pasture gets rested. That is only possible if the horses have somewhere else to stand, which is what a dry lot or sacrifice area is for.

It also earns its keep in wet spells, when grazing saturated ground does more damage in a weekend than a whole season of grazing does in dry weather.

Building one: how big a dry lot should be, and what to put under it.

If you rotate: how many paddocks, and how long to rest them.

For the days pasture does not cover: how much hay a horse needs.

Common questions

Beyond the two-acre rule.

How many acres per horse do you need?: Extension sources give different figures because they assume different management. Iowa State puts a mature horse on 1 to 2 acres of excellent, dense pasture, 2 to 2.5 acres of average pasture, and 3 or more acres of thin, unmanaged pasture. Penn State quotes 2 to 4 acres per 1,000 pound horse. About 2 acres is a fair starting point; your own figure depends on forage yield and grazing management.
How much grass does a horse eat per day?: Extension guidance puts a horse's daily hay intake at about 2 percent of bodyweight, and Iowa State treats 3 percent as a maximum. For a 1,000 pound horse that is about 20 pounds a day, which is far more forage than most people picture. This calculator uses the same 2 percent as a working figure for grazing.
Does rotational grazing reduce the acreage needed?: It can. Penn State describes rotational grazing as the system that yields the highest returns on available forage, because animals that stay on one field keep grazing their favorite plants while trampling and fouling the rest. How much land it saves is not a published constant. This calculator assumes 35 percent of forage is eaten under continuous grazing and 65 percent under rotation, which are its own working assumptions, and lets you switch between them.
Do I still need a dry lot if I have enough pasture?: Yes. A dry lot or sacrifice area lets you keep horses off wet ground, rest paddocks so they can regrow, and restrict grazing for horses prone to laminitis. Pasture acreage calculations assume the pasture gets rested, which is only possible if the horses have somewhere else to stand.

Read the guidance

Sources worth keeping nearby.

Maryland Extension Determining your Pasture Stocking Rate
Iowa State Extension How Many Horses Can Your Pasture Maintain?
Penn State Extension Grazing Systems for Horses