Grain loses weight as it dries because water is removed. The grain’s dry matter is treated as constant for a simple moisture-shrink estimate, while total weight changes with moisture content. The result helps estimate the final weight at a target moisture and the moisture-related weight reduction before considering storage, handling, or commercial charges.
Dry-matter balance formula
Final grain weight equals incoming weight multiplied by (100 minus current moisture percent) and divided by (100 minus target moisture percent). If 10,000 lb of grain at 20% moisture is dried to 15%, the dry matter is 8,000 lb. At 15% moisture, that same dry matter represents about 9,411.8 lb of grain, or a moisture-only weight reduction of about 588.2 lb.
Moisture shrink is not the whole drying bill
The dry-matter calculation estimates weight change from moisture. A buyer, elevator, or dryer may use a commercial shrink schedule or charge for drying, handling, storage, dockage, or other services. Those rules may differ from the simple dry-matter formula. Compare the same moisture basis, crop standard, scale weights, and contract terms when reviewing a grain ticket.
Use consistent moisture and test-weight figures
Moisture percentages should be entered on a wet basis as used for grain marketing unless the specific reference says otherwise. A moisture meter should be maintained and checked against the procedures recommended by its manufacturer or grain facility. Test weight affects bushel conversions; a bushel is a volume unit, so pounds per bushel depend on crop standards or actual test weight.
What the calculator does and does not tell you
The Grain Moisture Shrink Calculator estimates final weight, shrink percentage, bushel-equivalent weight reduction, and a price-based value. It does not calculate a dryer’s fuel cost or certify grain is safe to store. Safe grain storage depends on crop, moisture, temperature, aeration, storage duration, and facility management. Check local Extension recommendations for safe storage and drying practices.
This guide is educational and describes a calculation method. For local crop rates or operating decisions, use your state Extension service, current product labels, supplier records, and the sources listed on our research and sources page.