Horse Hay & Grain Daily Feeding Requirement Calculator
Underfeeding forage is one of the leading preventable causes of colic and gastric ulcers in horses, since their digestive systems are built for near-constant grazing. This calculator sizes daily hay needs by body weight and workload, then converts the total into practical flakes per feeding.
Feed your 1,100-lb horse 22.0 lbs of hay daily, split into about 5.5 flakes across morning and evening.
| Metric | Value |
|---|---|
| Body weight | 1,100 lbs |
| Workload category | maintenance |
| Intake factor | 2.00% |
| Daily hay needed | 22.0 lbs |
| Flakes per day (AM/PM split) | 5.5 (2.8/2.8) |
| Safe dry matter range | 16.5–27.5 lbs |
- 1.
DailyHay_lbs = BodyWeight_lbs × IntakeFactor - 2.
FlakesPerDay = DailyHay_lbs / AvgFlakeWeight_lbs - 3.
SafeRange = BodyWeight × [0.015, 0.025]
How to Use This Calculator
1. Enter your details
Use the labelled fields and units that match your situation.
2. Calculate instantly
The result, visual comparison, and working update as values change.
3. Review your result
Check assumptions, then copy, print, or share the calculation.
Formula & step-by-step maths
- IntakeFactor
- 0.02-0.03 depending on workload
Why forage percentage scales with workload
A horse at maintenance needs about 2% of body weight in forage daily just to maintain gut function and weight, while heavy training or lactation raises energy demands enough to push that closer to 2.5-3%.
The 1.5% dry matter safety floor
Veterinarians consider 1.5% of body weight in forage the absolute minimum to prevent gastric ulcers and colic from prolonged empty-stomach periods — this calculator flags any recommendation that falls below that floor.
Splitting feed across the day
Horses evolved to graze 16-18 hours a day in small amounts, so splitting the daily total into at least two, ideally three or more, feedings reduces digestive stress compared to one or two large meals.
Grass hay vs alfalfa considerations
Alfalfa is calorie- and protein-dense compared to grass hay, so horses on alfalfa may need a lower total weight of forage to meet the same energy needs — adjust workload category accordingly if switching hay types.
Daily hay needs by weight and workload
| Body weight | Maintenance (2.0%) | Moderate (2.25%) | Heavy training (2.5%) |
|---|---|---|---|
| 900 lbs | 18 lbs | 20.3 lbs | 22.5 lbs |
| 1,000 lbs | 20 lbs | 22.5 lbs | 25 lbs |
| 1,100 lbs | 22 lbs | 24.8 lbs | 27.5 lbs |
| 1,200 lbs | 24 lbs | 27 lbs | 30 lbs |
| 1,400 lbs (draft) | 28 lbs | 31.5 lbs | 35 lbs |
Frequently Asked Questions
Three worked examples
Same engine, three different starting points — useful if you want to see how sensitive the answer is before you type your own numbers in.
Example 1: horse body weight 858 lbs, workload / activity level "Maintenance (2.0%)"
On the lower / more conservative end. Feed your 858-lb horse 17.2 lbs of hay daily, split into about 4.3 flakes across morning and evening.
Example 2: horse body weight 1100 lbs, workload / activity level "Maintenance (2.0%)"
A typical middle-of-the-road setup. Feed your 1,100-lb horse 22.0 lbs of hay daily, split into about 5.5 flakes across morning and evening.
Example 3: horse body weight 1430 lbs, workload / activity level "Light Work (2.0-2.25%)"
On the higher / more demanding end. Feed your 1,430-lb horse 32.2 lbs of hay daily, split into about 8.0 flakes across morning and evening.
Quick answers about the Horse Hay Feeding
What exactly does the Horse Hay Feeding work out?
Underfeeding forage is one of the leading preventable causes of colic and gastric ulcers in horses, since their digestive systems are built for near-constant grazing. You enter horse body weight, workload / activity level and average flake weight and the result panel updates straight away, so you can compare two or three versions of the same question in a few seconds.
What do I need before I start?
Only 3 fields: horse body weight, workload / activity level and average flake weight. Nothing else is needed and nothing is stored.
How is it calculated — why forage percentage scales with workload?
A horse at maintenance needs about 2% of body weight in forage daily just to maintain gut function and weight, while heavy training or lactation raises energy demands enough to push that closer to 2. The same maths runs inside this page, so hand-checking the result on paper gives you the identical figure.
Why do two calculators give me different answers for horse Hay Feeding?
Veterinarians consider 1. Different sites pick different assumptions, so always check which method a calculator states before you trust the gap between two numbers.
What does the "Daily hay needs by weight and workload" table on this page tell me?
It is the reference range this tool works against — 5 rows from "900 lbs" (18 lbs) up to "1,400 lbs (draft)" (28 lbs). Use it to sanity-check whether the number you just calculated sits where you expected it to.
Which workload / activity level should I pick?
The dropdown offers 5 choices — Maintenance (2.0%), Light Work (2.0-2.25%), Moderate Work (2.25%), Heavy Training (2.5%) and Lactating Broodmare (2.5-3.0%). Pick the one that matches your real situation rather than the one you would like to be true; workload / activity level usually moves the final figure more than any other single input, so it is worth running it twice with the option above and below your guess.
Do I have to press a button or reload the page to see the result?
No. Horse Hay Feeding runs completely inside your browser, so the moment you change a value the cards recalculate — there is no submit step, no page reload and no waiting for a server round trip. That also means it keeps working on a weak or intermittent mobile connection.
Is it free, and do you keep what I type?
It is free with no sign-up, no app install and no usage limit. Nothing you enter into Horse Hay Feeding leaves your device — the calculation is JavaScript running locally, so there is no upload of your figures to DrHint or anyone else.
Can I use it on a phone?
Yes — the layout stacks to a single column on small screens and the number fields open the numeric keypad on both Android and iOS. Many people bookmark this page or add it to their home screen and re-open it whenever the question comes up.
Anything to be careful about with the result?
At maintenance (2% of body weight) with 4-lb flakes, that's about 22 lbs of hay, or roughly 5. Treat the output as a well-grounded estimate for planning, not as a professional, legal or medical decision on its own.
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