How the Grain Converter Works
The Grain Converter divides grain mass by grain bulk density, known in the grain trade as test weight. The default 0.77 kg/L fits wheat at the standard 60 lb per US bushel.
Pick the grain
Choose wheat, corn, soybeans, barley, oats or another crop from the table.
Use the test weight
Enter the density in kg/L, or divide lb/bu by 77.69 to get kg/L.
Enter the mass
Type the grain weight in kilograms from the weighbridge or yield monitor.
Read the volume
Divide the liters by 35.24 for US bushels, or by 1,000 for cubic meters.
Grain Converter Formula
The grain formula is V = m ÷ ρtest, and ρ (kg/L) = test weight (lb/bu) ÷ 77.69.
- ρtest
- Grain test weight as bulk density, kg/L
- 35.24
- Liters in one US bushel
Worked Examples
- Wheat (60 lb/bu): 1,000 kg ÷ 0.772 = 1,295 L = 36.8 bu.
- Corn (56 lb/bu): 25,000 kg ÷ 0.721 = 34,674 L (34.7 m³).
- Barley (48 lb/bu): 10 t ÷ 0.618 = 459 bu.
Grain Converter Conversion Table
1 tonne of wheat at 60 lb/bu fills 1,295 liters, or 36.8 US bushels. The table lists standard test weights for 10 crops.
| Crop | Standard Test Weight (lb/bu) | Bulk Density (kg/L) | Liters per Tonne | Bushels per Tonne | kg per Bushel |
|---|---|---|---|---|---|
| Wheat | 60 | 0.772 | 1,295 | 36.7 | 27.22 |
| Soybeans | 60 | 0.772 | 1,295 | 36.7 | 27.22 |
| Corn (shelled) | 56 | 0.721 | 1,387 | 39.4 | 25.40 |
| Sorghum | 56 | 0.721 | 1,387 | 39.4 | 25.40 |
| Rye | 56 | 0.721 | 1,387 | 39.4 | 25.40 |
| Canola | 50 | 0.644 | 1,554 | 44.1 | 22.68 |
| Barley | 48 | 0.618 | 1,619 | 45.9 | 21.77 |
| Rough rice | 45 | 0.579 | 1,726 | 49.0 | 20.41 |
| Oats | 32 | 0.412 | 2,428 | 68.9 | 14.51 |
| Sunflower (oil type) | 28 | 0.360 | 2,775 | 78.7 | 12.70 |
What is a Grain Converter?
A Grain Converter is a calculator that converts grain weight into storage volume using the test weight of the crop.
Test weight is the mass of a standard volume of grain, quoted in pounds per bushel in the US and kilograms per hectoliter elsewhere. 1 lb/bu equals 1.287 kg/hL.
Higher test weight signals plump, sound kernels. USDA grade No. 1 hard red winter wheat needs at least 60 lb/bu; No. 2 yellow corn needs at least 54 lb/bu.
What are the Uses of a Grain Converter?
There are 5 main uses of a Grain Converter.
Bin capacity
Farmers convert harvest tonnes into bin bushels.
Truck loading
Haulers check that hopper trailers reach weight before volume.
Grain marketing
Elevators convert contract bushels into tonnes.
Yield reporting
Agronomists convert kg/ha yields into bu/acre.
Seed planning
Growers convert seed sacks into drill hopper fills.