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Round bale weight calculator
Diameter, width, and density. A “1,000 lb bale” that is 4×5 of dry hay is usually lighter.
Round bale weight is volume times density. Measure diameter and width in feet (or convert), pick a density that matches how dry the hay is, and you get an estimated pounds per bale for feeding math — not a certified scale weight. On this place we use it when the hay calculator needs a real number and the dealer only said “4x5.” Also see TDN cost and stocking rate.
How to measure a round bale
Diameter is across the face, through the center, in feet — a 5-foot bale is 60 inches. Measure twice if it’s squashed. Width is the thickness of the roll, usually 4 feet on a 4×5. Don’t use the twine-to-twine guess. Dry grass hay is often around 10 lb/ft³; straw is lighter.
If you measured around the face instead of across it, this tool still wants diameter. Diameter is circumference divided by π (about 3.14). A true 5-foot face is about 15.7 ft around. Divide that circumference by 3.14 and you are back at 5.
Worked example: a 4×5 of dry grass
Diameter 5 ft, width 4 ft, density 10 lb/ft³ (the dry grass preset). The calculator uses cylinder volume times density: π × (2.5 ft)² × 4 ft is about 78.5 cubic feet. Times 10 is about 785 lb. The result rounds volume to 79 ft³ and the bale to 785 lb. Example only — punch your measures in the calculator. A dealer “1,000 lb bale” is often lighter when the hay is dry and loosely packed.
Density presets
Wetter hay or a tighter wrap gets a higher density estimate. It is still not a scale. The rows below are the presets on the form, and the pounds are that same 5 ft by 4 ft bale run through this tool. The term is round bale density.
| Preset | lb/ft³ | This 4×5 |
|---|---|---|
| Straw | 6 | 471 lb |
| Dry grass hay | 10 | 785 lb |
| Mixed | 11 | 864 lb |
| Wetter / tight wrap | 13 | 1,021 lb |
After you know bale weight
Put the pounds into the winter hay calculator and set waste so you do not under-buy. What that hay costs per pound of energy is TDN cost. Whether to bale it or buy it is make vs buy. How many animals the pasture can carry is stocking rate. Print the round-bale field sheet if you are measuring in the pasture. For a deal priced by the pound, use a scale.
Questions
How much does a 4x5 round bale weigh?
It depends on density and moisture. A 5 ft by 4 ft bale at the dry-grass preset (10 lb/ft³) is about 785 lb in this calculator — hundreds of pounds, not a flat 1,000. Wetter or tighter bales weigh more. Run diameter, width, and density.
Should I use diameter or circumference?
This tool wants diameter and width. If you measured circumference, divide by π (~3.14) to get diameter.
Is calculator weight good enough for feeding?
Yes for planning hay needs. For buying or selling by the pound, use a scale.
How do I measure diameter and width on a round bale?
Diameter is across the face through the center (a 5-foot bale is 60 inches). Width is the thickness of the roll (often 4 feet on a 4×5). Measure twice if the bale is squashed.
What density should I pick for dry grass hay?
Start around 10 lb/ft³ (the dry grass preset). Use mixed (about 11) or wetter/tight (about 13) if the bale is heavier-packed or damper. Straw is lighter (about 6).
Why isn’t every 4×5 a 1,000 lb bale?
Weight is volume times density. Dry, loosely packed grass often lands well under a marketing thousand-pound label. A 5 ft by 4 ft bale at 10 lb/ft³ is about 785 lb here. Run your measures in the calculator.
Can I use this weight in the hay calculator?
Yes for planning. Enter the estimated pounds per bale into the cattle hay calculator and adjust waste. For buying or selling by the pound, use a scale.
Does moisture change the answer?
Yes. Wetter hay weighs more per cubic foot and the estimate moves. Weigh a load when money changes hands.
Planning only. Weigh a load when you can. Density moves with moisture, species, and how hard the baler packed it.
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