Grain Conversion Calculator (bushels ↔ tonnes, kg, lb for wheat, corn, soybeans…)

Understanding the grain conversion calculator — concept and principle

This calculator converts grain quantities between bushels, metric tonnes, kilograms, pounds and US short tons for common crops such as wheat, soybeans, corn, barley and oats. It also shows bushels per tonne, kilograms per bushel and the volume the bushels would occupy. Farmers, grain traders, agronomy students and anyone reading US crop reports use it.

Bushels are weighed by crop — with the default inputs: 136.078 t.

How it is calculated

Weight per bushel (kg) = standard pounds per bushel × 0.45359237
Weight = bushels × kg per bushel; bushels = weight ÷ kg per bushel
Bushels per tonne = 1,000 ÷ kg per bushel
Volume = bushels × 0.035239 m³ (US bushel of 2,150.42 in³)

Standard weights: wheat and soybeans 60 lb; shelled corn, sorghum, rye and flaxseed 56 lb; barley and buckwheat 48 lb; rough rice 45 lb; oats 32 lb.

The principle

A bushel was originally a volume measure, but grain trade uses a standard weight per bushel for each crop, set by the USDA, so that "a bushel of wheat" always means 60 pounds. That makes converting between bushels and tonnes a matter of one factor per crop: for wheat, 1 tonne = 36.744 bushels; for corn, 39.368. These standard weights are averages and differ from the test weight of a particular lot, which varies with moisture and quality.

Worked example

Defaults: wheat (60 lb/bu), 5,000 bushels.

Kg per bushel = 60 × 0.45359237 = 27.216.
Weight = 5,000 × 60 = 300,000 lb = 136,078 kg = 136.078 t.
Short tons = 300,000 ÷ 2,000 = 150.
Bushels per tonne = 1,000 ÷ 27.216 = 36.744.
Volume = 5,000 × 0.035239 = 176.2 m³.

Bushels: 5,000.

Each point is the calculator re-run with only “Amount of grain” changed; the gold point is the default example. Change the inputs above and this chart follows your numbers.

Amount of grain	Bushels
1,250	1,250
2,500	2,500
3,750	3,750
5,000	5,000
6,250	6,250
7,500	7,500
10,000	10,000

How to read the result

Use the tonnes figure to compare US yields or prices with international ones quoted per tonne. For example, a price per bushel of wheat can be multiplied by 36.744 to get a price per tonne. The volume figure helps with bin capacity, but actual storage needs depend on packing and moisture.

Common mistakes

Using the wheat factor for corn or soybeans.
Mixing short tons and metric tonnes.
Treating the standard weight as the test weight of your grain.
Using an Imperial bushel instead of the US bushel for volume.

Keep in mind: Standard bushel weights are conventions for trade; contracts may specify moisture adjustments and test weights. Check your contract.

Frequently asked questions

How many bushels of wheat are in a tonne?

About 36.74, using the standard 60 lb per bushel.

How many bushels of corn are in a tonne?

About 39.37, using 56 lb per bushel.

Why do bushel weights differ by crop?

Different grains have different densities, so the USDA sets a standard weight for each.

Sources: USDA Economic Research Service, Agricultural Handbook No. 697 (1992), Weights, Measures, and Conversion Factors for Agricultural Commodities and Their Products · NIST Special Publication 811 (2008 ed.), Appendix B.9

Checked 9 Nov 2026. USDA Economic Research Service, Agricultural Handbook No. 697 (1992), Weights, Measures, and Conversion Factors for Agricultural Commodities and Their Products, Table 6 (weights per bushel) and Table 5 (1 metric ton = 36.7437 bu of wheat, 39.368 bu of corn); NIST Special Publication 811 (2008 ed.), Guide for the Use of the International System of Units (SI), Appendix B.9 “Factors for units listed by kind of quantity or field of science” — bushel (U.S.), pound (avoirdupois), ton (short).

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