Moisture Shrink & Drying Loss Calculator
Calculate how much weight and bushels you lose when drying grain from a high moisture content to a market-acceptable level. This calculator uses the standard moisture shrink formula and shows the revenue impact of drying.
Results
Formula & How It Works
Shrink % = [(Initial Moisture% − Final Moisture%) ÷ (100 − Final Moisture%)] × 100
This formula accounts for the fact that dry matter is conserved — only water is removed. The denominator (100 − final moisture) converts to dry matter basis.
Final Weight = Initial Weight × (1 − Shrink% ÷ 100)
Weight Loss = Initial Weight − Final Weight
Bushels = Weight (lb) ÷ Test Weight (lb/bu)
Calculation Example
50,000 lb of corn at 25% moisture dried to 15%: Shrink = [(25 − 15) ÷ (100 − 15)] × 100 = (10 ÷ 85) × 100 = 11.76%.
Final weight = 50,000 × (1 − 0.1176) = 44,120 lb. Weight loss = 5,880 lb. At 56 lb/bu: Initial = 893 bu, Final = 788 bu. At $4.50/bu: Revenue loss = 105 bu × $4.50 = $472.
How to Use This Calculator
1. Enter the initial moisture percentage of the grain as harvested. 2. Enter the target final moisture (typically 15% for corn, 13% for soybeans). 3. Enter the initial weight. 4. Add sale price and test weight for revenue analysis. Click Calculate.
About This Tool
Moisture shrink is a critical factor in grain marketing and drying economics. When grain is dried, only water is removed — dry matter (and the nutrients it contains) is conserved. The shrink formula correctly accounts for this by using dry matter basis in the denominator. Understanding shrink helps you compare the cost of on-farm drying versus selling wet grain at a discount, and evaluate whether drying revenue covers drying costs (fuel, electricity, labor).
Applicability: Relevant for grain storage operations in North America and Europe.
References & Sources:
- Source: USDA Grain Inspection, Packers and Stockyards Administration (GIPSA), Grain Quality and Moisture Standards, 2024.
- Reference: University of Minnesota Extension, Grain Drying and Storage Management, 2024.
- Reference: ASABE Standard S448.1, Grain Storage and Handling Systems.
Reviewed by Agricalc Editorial Team — Agricultural engineers and agronomists with 10+ years of field experience. Our team verifies every calculator formula against peer-reviewed extension publications. For site-specific advice, consult your local agronomist.
Common Mistakes & Tips
Common mistakes: Using simple subtraction (initial − final) instead of the correct formula — this underestimates shrink because it doesn't account for dry matter conservation. Forgetting that test weight can change during drying — dried grain may have higher test weight. Confusing moisture shrink with handling loss — shrink is water removal only, not physical loss from spills or augers. Ignoring that different commodities have different target moistures.
References & Sources
- FAO (Food and Agriculture Organization) — Agricultural production and nutrition guidelines
- USDA NRCS — Field Office Technical Guide and conservation practice standards
- Land-Grant University Cooperative Extension System — crop and livestock recommendations
- USDA NRCS — Soils
- FAO — Soils Portal
