Round Bale Weight Calculator
Estimate what a bale actually weighs from its dimensions and how tightly it was rolled.
Your numbers
5.0 ft × 5.0 ft round bale at 9.0 lb/ft³
884 lb per bale
- Dry matter in the bale
- 778 lb DM
- Bales per ton
- 2.26 bales
- Bale volume
- 98 ft³
- The outer 6 inches of this bale holds about 36% of the hay — that is the part at risk when bales sit outside uncovered.
- Verify density once by weighing three bales; after that a tape measure weighs your whole hay crop.
Show the math
- Volumeπ × (5.0 ÷ 2)² × 5.0 ft = 98.2 ft³
- As-fed weight98.2 ft³ × 9.0 lb/ft³ = 884 lb
- Dry matter weight884 lb × 88% = 778 lb DM
- Bales per ton2,000 ÷ 884 = 2.26 bales
Assumptions this calculator used
Nothing here is hidden. Change any figure you have better local data for.
Depth of the outer layer used to show how much hay sits in the weathering zone. Source: University of Kentucky Extension AGR-171, outside hay storage.
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How to calculate round bale weight
A bale's weight is its volume times its density. Volume comes off a tape measure; density comes from the crop and how hard the baler packed it. Get density right once by weighing a few bales and you can price, budget and haul hay without a scale from then on.
Round: volume ft³ = π × (diameter ÷ 2)² × width
Square: volume ft³ = length × width × height
Weight lb = volume × density (lb/ft³)
Worked example
A 5 ft by 6 ft round bale has a volume of π × 2.5² × 6, or 118 cubic feet. Typical grass hay at 9 lb per cubic foot puts it at roughly 1,060 lb. At 88% dry matter that bale carries about 933 lb of actual feed, and it takes 1.9 bales to make a ton.
Common mistakes
- Using the baler's nominal size. Bales sag and settle; measure the bale on the ground.
- Assuming one density for every crop. Cornstalks and alfalfa off the same baler differ by 60% in weight per cubic foot.
- Comparing wet and dry bales by scale weight. Convert to dry matter before you compare or price anything.
- Forgetting that diameter is squared. Buying "5 ft bales" and receiving 4.5 ft bales is a 19% shortfall in hay, not 10%.
Round bale weight by diameter, width and density
As-fed pounds per bale. Read across at your bale dimensions and down to the density that matches your crop and baler.
| Bale size (dia × width) | Volume | 7 lb/ft³ (loose) | 9 lb/ft³ (typical) | 11 lb/ft³ (tight) |
|---|---|---|---|---|
| 4 × 4 ft | 50 ft³ | 352 lb | 452 lb | 553 lb |
| 4 × 5 ft | 63 ft³ | 440 lb | 565 lb | 691 lb |
| 4 × 6 ft | 75 ft³ | 528 lb | 679 lb | 830 lb |
| 5 × 4 ft | 79 ft³ | 550 lb | 707 lb | 864 lb |
| 5 × 5 ft | 98 ft³ | 687 lb | 883 lb | 1,080 lb |
| 5 × 6 ft | 118 ft³ | 825 lb | 1,060 lb | 1,296 lb |
| 6 × 5 ft | 141 ft³ | 990 lb | 1,272 lb | 1,555 lb |
| 6 × 6 ft | 170 ft³ | 1,187 lb | 1,527 lb | 1,866 lb |
Calculators to run next
- Hay Bale CalculatorUse to convert between tons quoted by a seller and bales you actually load.
- Hay Cost Per Ton CalculatorUse to compare two loads priced per bale, or hay quoted at different moistures.
- Hay Waste CalculatorUse when deciding whether a cone ring or cradle feeder pays for itself.
- Hay Moisture CalculatorUse before comparing prices — wet hay carries tons of water priced as forage.
- Hay Storage Loss CalculatorUse when weighing a shed, tarp or gravel pad against bales sitting on dirt.
- Winter Hay CalculatorStart here when you need to size the stack for the winter before you buy.
Guides that use this calculator
- Budgeting a Winter Hay Supply Before the First FrostBales per cow per day, waste by feeding method, and how much of the stack a February cold snap really takes.
- Pricing Hay by the Ton Instead of by the BaleTwo loads at the same price per bale can differ 40 percent on cost per ton of dry matter. Here is the conversion.
Questions ranchers ask
How much does a 5x5 round bale weigh?
A 5 ft by 5 ft grass hay bale at a typical 9 lb per cubic foot holds about 883 lb. The same dimensions in tightly rolled alfalfa at 11 lb/ft³ come in near 1,080 lb, and a loose, dew-baled grass bale at 7 lb/ft³ can be under 700 lb. Dimensions alone never tell you the weight — density does.
How much does a 4x5 or 5x6 round bale weigh?
At 9 lb/ft³, a 4 ft diameter by 5 ft wide bale is about 565 lb and a 5 ft by 6 ft bale about 1,060 lb. Note that a 5x6 holds roughly 20% more hay than a 5x5 even though only the width changed, and a 6x5 holds 44% more than a 5x5 because diameter is squared in the volume.
Why is diameter more important than width?
Volume is π × radius² × width. Radius is squared, so going from a 5 ft to a 6 ft bale at the same width adds 44% more hay, while going from 5 ft to 6 ft of width adds only 20%. That is also why the outer foot of a big bale holds so much of the total.
How much hay is in the outer six inches of a bale?
On a 5 ft bale, the outer 6 inches is about 36% of the total volume. That is the layer that weathers if the bale sits outside uncovered, which is why storage losses on unprotected bales are so much larger than most people expect from looking at the crust.
What is a typical round bale density?
Field-baled grass hay typically runs 8 to 10 lb per cubic foot. Alfalfa and tightly wrapped bales from a high-density baler go 10 to 12. Cornstalk bales are often 6 to 8. Baleage is far heavier per cubic foot only because of its water — its dry matter density is similar.
How do I check the density of my own bales?
Weigh several bales on a loader scale or across a livestock scale, then divide by the calculated volume for their dimensions. Do it once for each crop and each baler and you can weigh the whole hay crop with a tape measure from then on.
Does moisture change the bale weight I should plan on?
It changes the scale weight, not the feed. A 1,000 lb bale at 85% dry matter holds 850 lb of feed; the same bale at 78% dry matter holds 780 lb and is much more likely to heat. Plan rations and hay purchases on the dry matter weight this tool reports.
Are square bales easier to weigh accurately?
Yes — the volume math is simple length × width × height, and large squares from a given baler are far more consistent than round bales from a variable-chamber machine. That consistency is one reason hay traded by the semi-load is usually in 3x4 or 4x4 squares.
Weigh what you buy — the same way you should weigh what you bid on
Hay bought by the bale and cattle bought by the head are the same trap: the unit hides the substance. Every lot on Agrilot carries actual weights, measured frame data and an independent condition report, so you are bidding on documented pounds rather than a photograph.