Grain Shrinkage Calculator
Enter the initial weight and moisture content along with the target moisture level to find the final weight and shrinkage.
How grain shrinkage is calculated
This calculator uses the dry-matter balance formula: final weight = initial weight × (100 − initial moisture%) / (100 − final moisture%). It works because the amount of dry matter in the grain doesn't change during drying — only the water content does, so the dry-matter proportion stays constant on both sides of the equation.
Shrinkage represents the weight lost as water evaporates during drying. This matters for grain marketing and storage, since grain is typically bought and sold by weight, and drying reduces that weight even though the amount of actual grain solids hasn't changed.
Frequently asked questions
Why does weight decrease when moisture content decreases?
Removing water through drying reduces the total weight of the grain, since water makes up part of that weight. The dry matter (the actual grain solids) stays the same amount — only the water portion is lost.
What's a typical moisture target for stored grain?
Safe storage moisture targets vary by grain type — corn is often dried to around 15%, while wheat and soybeans typically target around 13%. Check guidance specific to your grain type and storage duration.
Does this formula work for any starting and ending moisture levels?
Yes, as long as the final moisture is lower than the initial moisture (standard drying) and both are below 100%. If final moisture is higher than initial (rewetting rather than drying), the formula still works mathematically, just producing a weight increase instead of a decrease.