When grain comes in wetter than the marketing standard, its weight has to be shrunk to the standard moisture before it can be priced fairly. This tool applies the dry-matter shrink method, adds any handling shrink the elevator charges, and converts the net weight to bushels at the crop’s standard test weight.
How it works
The dry-matter method holds the bone-dry weight constant while restating the grain at the standard moisture:
corrected wt = gross wt × (100 − wet moisture) / (100 − standard moisture)
net wt = corrected wt × (1 − handling shrink %)
bushels = net wt / standard test weight per bushelBecause only water is removed, a load delivered above standard moisture always loses weight: the wetter the grain, the larger the shrink. Standard test weights are 56 lb/bu for corn and sorghum and 60 lb/bu for soybeans and wheat.
Standard marketing moistures at a glance
| Crop | Standard moisture | Test weight per bushel |
|---|---|---|
| Corn | 15.5% | 56 lb |
| Soybeans | 13.0% | 60 lb |
| Wheat | 13.5% | 60 lb |
| Grain sorghum | 14.0% | 56 lb |
These are the US marketing standards established by USDA grade specifications. Grain settled at these moistures resists spoilage in storage and is the accepted pricing basis for futures-market contracts.
Worked example — 10,000 lb corn at 20% moisture
A semi load of corn probed at 20% moisture, delivered to an elevator using a 1% handling shrink:
- Moisture correction: 10,000 × (100 − 20) / (100 − 15.5) = 10,000 × 80 / 84.5 = 9,467 lb
- Handling shrink (1%): 9,467 × 0.99 = 9,372 lb net
- Bushels: 9,372 / 56 = 167.4 bu
The producer receives payment on 167.4 bushels, not on the 178.6 bushels the gross weight would imply at 56 lb/bu. The 11.2-bushel difference is the combined moisture and handling shrink.
Why the moisture probe matters so much
A single percentage point of extra moisture at delivery has a compounding effect. At 10,000 lb, the correction factor for 21% moisture versus 20% moisture is:
- 20%: factor = 80/84.5 = 0.9467 → 9,467 lb
- 21%: factor = 79/84.5 = 0.9349 → 9,349 lb
One additional point of moisture costs about 118 lb, or roughly 2.1 bushels on a 10,000 lb load. On a large delivery, that is real money. Probing at multiple spots in the truck — especially from the front, middle, and rear where moisture stratifies during transport — produces a more representative average than a single probe.
Handling shrink: what to confirm with your buyer
Handling shrink is an elevator-specific charge, not a universal formula. Common rates range from 0.3% to 1.5% depending on the facility and the season. Some elevators apply it only to drying loads; others apply it to all incoming grain. Before running this tool against a contract, verify the exact handling shrink rate your specific buyer uses. The standard moisture and standard test weight are nearly universal, but the handling shrink is negotiable and contract-specific.
Using this for invoicing and settlement
The bushel figure this tool produces — net weight divided by standard test weight — is the number that appears on a grain scale ticket and settlement sheet. Cross-checking it with this calculator before accepting a settlement confirms that the elevator’s arithmetic is correct and that your probe moisture and their probe moisture are close. A discrepancy of more than one to two bushels on a typical load is worth investigating.