Accurately calculate moisture shrinkage, handling loss, and net value
Total weight of grain before drying.
Please enter a valid positive weight.
Current moisture level of the grain (e.g., 25%).
Initial moisture must be higher than target moisture.
Desired moisture level for storage or sale (Standard Corn: 15.0%).
Estimated loss from dust and fines (typically 0.5% – 1.0%).
Current market price per bushel or lb.
Final Dry Weight
877.19 Units
Total Weight Loss
122.81 Units
Total Shrinkage %
12.28%
Water Removed
117.65 Units
Value of Weight Lost
$552.65
Calculation uses the standard constant dry matter formula plus handling loss.
Formula: Final Weight = Initial Weight × ((100 – Initial%) / (100 – Target%)) × (1 – Handling%).
Weight Loss Breakdown
Shrinkage Schedule (Per 1000 Units)
Moisture Reduction
Water Loss
Handling Loss
Remaining Weight
Table shows projected weight loss at various moisture intervals based on current inputs.
What is a Grain Drying Weight Loss Calculator?
A grain drying weight loss calculator is an essential agricultural tool used by farmers, elevator operators, and commodity traders to estimate the reduction in grain weight that occurs during the drying process. When grain—such as corn, soybeans, or wheat—is harvested at high moisture levels, it must be dried to a safe moisture content for storage or sale.
This process results in "shrinkage," which consists of two parts: water shrink (the actual weight of water evaporated) and handling loss (often called invisible shrink, which includes dust, fines, and small particles lost during mechanical handling). Understanding these numbers is critical because grain is sold by weight. A reduction in weight directly correlates to a reduction in revenue, often referred to as "shrink loss."
This calculator helps you determine the exact final weight of your crop after drying, allowing for accurate inventory management and financial forecasting.
Grain Drying Weight Loss Formula and Mathematical Explanation
The calculation of grain shrinkage is based on the principle of Constant Dry Matter. The theory assumes that while water is removed, the amount of dry matter (the grain fiber, starch, oil, etc.) remains constant (excluding handling loss).
The Core Formula
To calculate the weight of the grain after removing water, we use the following formula:
However, real-world scenarios include "invisible" losses due to augers, fans, and movement. Therefore, the comprehensive formula used in this grain drying weight loss calculator is:
Net Final Weight = Final Weight (Water Only) × (1 – (Handling Loss % / 100))
Variable Definitions
Variable
Meaning
Unit
Typical Range
Initial Weight
Wet weight of grain at harvest
Lbs / Bushels
Any
Initial Moisture
Water content at harvest
Percentage (%)
15% – 35%
Target Moisture
Desired water content for storage
Percentage (%)
13% – 15%
Handling Loss
Mechanical loss (dust/fines)
Percentage (%)
0.5% – 1.0%
Practical Examples (Real-World Use Cases)
Example 1: Drying Corn from 25% to 15%
A farmer harvests 10,000 bushels of corn at 25% moisture. He needs to dry it down to 15% for standard storage. He estimates a 0.5% handling loss.
Result: The farmer loses approximately 1,220 bushels to shrinkage. At $5.00/bu, this is a value reduction of $6,100 (though necessary to prevent spoilage).
Example 2: Soybean Harvest Adjustment
A producer delivers 50,000 lbs of soybeans at 16% moisture. The buyer requires 13% moisture.
How to Use This Grain Drying Weight Loss Calculator
Enter Wet Weight: Input the total weight of the grain as measured at the scale (lbs, bushels, or tonnes).
Input Moisture Levels: Enter the current moisture percentage found via testing and the target moisture percentage (usually 15% for corn, 13% for soybeans).
Set Handling Loss: Adjust the invisible loss percentage. If you are unsure, leave it at the industry standard of 0.5%.
Add Price (Optional): Enter the current market price to see the financial value of the weight that will "disappear" during drying.
Analyze Results: Review the "Final Dry Weight" and "Value of Weight Lost" to make informed storage or selling decisions.
Key Factors That Affect Grain Drying Results
Several variables influence the final outcome of your grain drying weight loss calculation:
Initial Moisture Content: The higher the starting moisture, the more water weight must be removed. Corn harvested at 30% loses significantly more weight than corn harvested at 20%.
Target Moisture Standards: Different buyers and storage facilities have different requirements. Drying below the requirement (over-drying) results in unnecessary weight loss and lost revenue.
Mechanical Handling: Older dryers or aggressive auger systems can increase handling loss (invisible shrink) by creating more dust and fines.
Grain Type: Corn, wheat, and soybeans have different physical properties that affect how easily they release moisture and how much dry matter is lost during handling.
Drying Temperature: High-temperature drying is faster but can cause kernel stress cracks, leading to higher handling losses later in the supply chain.
Field Dry Down vs. Mechanical Drying: Allowing grain to dry in the field reduces mechanical drying costs and shrinkage but increases the risk of field loss (lodging, wildlife damage).
Frequently Asked Questions (FAQ)
What is the difference between water shrink and invisible shrink?
Water shrink is the weight reduction caused solely by the evaporation of moisture. Invisible shrink (or handling loss) is the loss of physical grain material (dust, chaff, fines) that occurs during the mechanical process of moving and drying the grain.
Why do elevators use a shrink factor (e.g., 1.4%) instead of the exact formula?
Elevators often use a "shrink factor" (like 1.4% or 1.5% per point of moisture) to simplify calculations and cover both water loss and handling loss in one number. This factor is usually slightly higher than the mathematical water loss to ensure the elevator covers their operating costs.
Does this calculator work for all grains?
Yes. The math behind the grain drying weight loss calculator applies to corn, soybeans, wheat, barley, and oats, as it is based on the physics of moisture removal.
What is the ideal moisture content for corn storage?
For short-term storage (winter), 15.5% is acceptable. For long-term storage (up to a year), corn should be dried to 13% – 14% to prevent mold and spoilage.
How much value do I lose by over-drying grain?
Over-drying is costly. If you dry corn to 13% when the market accepts 15%, you are selling 2.3% less weight than necessary, plus paying for the extra fuel to remove that water. This is a direct hit to profit margins.
Can I use this for metric tonnes?
Yes. The calculator is unit-neutral. If you enter weight in tonnes, the result will be in tonnes.
What is "Constant Dry Matter"?
It is the assumption that the weight of the dry material (fiber, starch, etc.) does not change during drying; only the water weight changes. This is the basis for the standard shrinkage formula.
How does handling loss affect the bottom line?
While 0.5% seems small, on a 100,000-bushel harvest, that is 500 bushels. At $5/bu, that is a $2,500 "invisible" cost that must be accounted for in net profit calculations.
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