Horse Feed Calculator - Online Daily Hay & Grain Ration

A horse typically needs 1.5% to 2.5% of its body weight in hay per day (dry matter basis). For a 1,100-pound horse, this translates to approximately 16.5 to 27.5 pounds of hay daily. The exact amount depends on the horse's activity level, age, metabolism, and the quality of the hay. Horses at maintenance (no work) need about 1.5–1.7%, while horses in heavy work may require 2.3–2.5%. Always provide good-quality forage as the foundation of your horse's diet.

The ideal forage-to-concentrate ratio varies by workload:

• Maintenance / Light work: 85–95% hay, 5–15% grain
• Moderate work: 70–80% hay, 20–30% grain
• Heavy work: 60–70% hay, 30–40% grain

Forage should always make up the majority of the diet to maintain digestive health. Horses are hindgut fermenters designed to process fibrous forage continuously. Feeding too much grain at once increases the risk of colic and laminitis. A good rule of thumb is to never feed more than 0.5% of body weight in grain per meal (about 5–6 lbs for an 1,100-lb horse).

You can estimate your horse's weight using a weight tape or the formula: Heart Girth (inches)² × Body Length (inches) ÷ 330 = Weight in pounds. Once you know the weight, use a horse feed calculator (like the one above) to determine daily rations. The calculator factors in life stage, activity level, and body condition to give you a tailored hay and grain recommendation. Regularly weighing your horse or using a body condition score (BCS) chart helps ensure your feeding program is on track.

Grain requirements range from 0 to 1.2% of body weight daily, depending on activity:

• Idle horse: 0–2 lbs (often no grain needed if hay is good quality)
• Light work: 2–5 lbs
• Moderate work: 5–8 lbs
• Heavy work: 8–12 lbs

Always split grain into 2–3 smaller meals rather than one large feeding. This reduces the risk of digestive upset. Choose a commercial concentrate formulated for your horse's life stage, or work with a nutritionist to blend appropriate grains. Remember: grain is a supplement to forage, not a replacement.

A standard small-square-bale flake weighs approximately 4–5 pounds. So if your horse needs 20 pounds of hay per day, that's about 4–5 flakes. However, flake weight varies significantly by bale density, hay type, and baler settings. Alfalfa flakes tend to be heavier (5–7 lbs), while grass hay flakes may be lighter (3–5 lbs). It's better to weigh your flakes once to understand what your bales actually deliver, then use that knowledge for daily feeding. For round bales, estimate intake by monitoring consumption rate over several days.

Pregnant mares in their last trimester need about 15–25% more feed than maintenance levels to support fetal growth. Lactating mares have the highest nutritional demands, requiring 30–50% more energy than a maintenance horse. A lactating mare producing milk for a nursing foal may need 2.5–3.5% of her body weight in total feed daily, with increased protein (14–16% crude protein) and calcium. High-quality alfalfa hay and a balanced broodmare concentrate are recommended. Always consult your veterinarian for specific recommendations during these critical periods.

An average adult horse drinks 5 to 15 gallons (20–55 liters) of water per day. Water needs increase with:

• Hot weather and sweating (up to 20+ gallons)
• Heavy work and exercise
• Lactation (nursing mares need significantly more)
• High hay diets (dry forage increases thirst)

A simple guideline: horses need approximately 0.5–1 gallon of water per 100 lbs of body weight daily. Always provide free-choice access to clean, fresh water. Dehydration can lead to impaction colic, reduced performance, and serious health issues. In winter, ensure water sources aren't frozen and consider heated buckets or tank heaters.

Both are excellent forages, but they serve different purposes:

• Alfalfa (legume hay): Higher in protein (16–20%), calcium, and digestible energy. Great for growing horses, lactating mares, and hard-working horses. May be too rich for easy keepers and can lead to weight gain if overfed.
• Timothy (grass hay): Lower in protein (7–11%), higher in fiber. Excellent for maintenance horses, easy keepers, and as a base forage. Less likely to cause digestive issues when fed in large amounts.

Many horse owners feed a mix of alfalfa and grass hay to balance protein and fiber. The best choice depends on your horse's nutritional needs, activity level, and any health conditions (e.g., horses with kidney issues may need lower calcium hay). Always test your hay for nutrient content when possible.

Horses are natural trickle feeders designed to graze for 14–18 hours per day. In a domestic setting, aim for:

• Hay: 2–4 portions spread throughout the day (morning, afternoon, evening)
• Grain: 2–3 small meals (never more than 5–6 lbs per feeding for an average horse)

Feeding smaller, more frequent meals mimics natural grazing behavior, reduces boredom and stable vices (cribbing, weaving), and lowers the risk of gastric ulcers and colic. If possible, use slow-feed hay nets to extend eating time and provide consistent roughage access. Avoid leaving a horse without forage for more than 4–6 hours.

Signs of underfeeding: visible ribs, sunken withers, dull coat, lethargy, poor performance, weight loss, and a body condition score (BCS) of 3 or below on the 1–9 Henneke scale.

Signs of overfeeding: cresty neck, fat pads around the tailhead and shoulders, difficulty feeling ribs, labored breathing during exercise, increased laminitis risk, and a BCS of 7 or above.

The ideal BCS for most horses is 5–6 (ribs easily felt but not visible, slight fat cover). Use body condition scoring monthly to adjust feed rations. Sudden changes in weight or condition warrant a veterinary check-up, as underlying health issues (dental problems, parasites, metabolic disorders) can affect nutritional status.

Yes. Senior horses (20+ years) often face challenges like dental wear, reduced digestive efficiency, and metabolic changes. Key considerations include:

• Provide softer, more digestible forage (soaked hay cubes, chopped hay, or haylage) if teeth are worn
• Increase feeding frequency to 3–4 times daily with smaller portions
• Use a senior-specific concentrate with higher digestibility, added prebiotics, and joint support nutrients
• Monitor for PPID (Cushing's disease) and insulin resistance, which may require low-NSC (non-structural carbohydrate) diets
• Ensure adequate protein intake (12–14%) to maintain muscle mass

Senior horses may need 10–20% more feed than adult maintenance horses to maintain weight, but this should be adjusted based on individual body condition. Regular dental care is essential for this age group.