Calculating corn yield by weight with moisture adjustment
Total weight of grain from scale ticket or cart (e.g., 56,000 lbs).
Please enter a valid positive weight.
Current moisture percentage (Standard base is 15.5%).
Moisture must be between 0 and 100.
Number of acres harvested for this load/batch.
Please enter a valid number of acres.
Current market price per bushel.
Please enter a valid price.
Yield Per Acre (Dry/Adjusted)
0.0 Bu/Acre
Total Dry Bushels
0
Total Revenue
$0.00
Shrink Loss
0 Bu
Formula Used: Adjusted Weight = Wet Weight × ((100 – Moisture%) / (100 – 15.5%)). Final bushels derived by dividing adjusted weight by 56 lbs.
Comparison of Wet Bushels (Raw) vs. Marketable Dry Bushels
Metric
Value
Notes
What is calculating corn yield by weight?
Calculating corn yield by weight is the process of determining the precise volume of marketable grain harvested from a field based on the mass measured at a scale, adjusted for moisture content. Unlike yield monitors which estimate volume based on flow sensors, calculating corn yield by weight provides the "cash" figure—the actual amount of grain a farmer can sell.
This calculation is essential for farmers, agronomists, and grain elevators because corn is rarely harvested at the standard base moisture of 15.5%. When corn is harvested "wet" (above 15.5%), the water weight must be subtracted to determine the "dry" bushels. Understanding the process of calculating corn yield by weight ensures that financial projections are accurate and that storage decisions are based on net inventory rather than gross weight.
Common misconceptions include assuming that dividing total weight by 56 (the standard bushel weight) gives the final yield. This fails to account for moisture shrinkage, leading to inflated yield estimates. Accurate calculating corn yield by weight must always include a moisture adjustment factor.
Calculating Corn Yield by Weight Formula
To perform the calculation accurately, we use the dry matter formula. This mathematically removes the water weight to standardize the grain to 15.5% moisture.
Practical Examples of Calculating Corn Yield by Weight
Example 1: The Wet Harvest
Farmer Smith harvests 100,000 lbs of corn from a 20-acre field. The moisture tester reads 22.5%. He wants to know his yield for crop insurance records.
Interpretation: If Farmer Smith had simply divided 100,000 by 56, he would have estimated 1,785 bushels. Calculating corn yield by weight correctly shows he has ~148 bushels less due to water weight.
Example 2: The High-Yield Field
An elevator receives a truck with 55,000 lbs of corn at 16.0% moisture.
Factor: (100 – 16.0) / 84.5 = 0.9940
Adjusted Weight: 55,000 × 0.9940 = 54,674 lbs
Dry Bushels: 54,674 / 56 = 976.3 bushels
How to Use This Corn Yield Calculator
Enter Harvested Weight: Input the total pounds from your weigh tickets. If you don't have a scale, you can estimate based on grain cart capacity, though this reduces accuracy when calculating corn yield by weight.
Input Moisture Content: Enter the percentage from your moisture tester. Be precise; even 0.5% changes the financial outcome significantly.
Specify Acres: To get the efficiency metric (Bushels Per Acre), input the exact size of the harvested area.
Set Price: Enter the current cash bid or contract price to see the total revenue potential.
Analyze Results: Use the "Dry Bushels" figure for storage planning and the "Yield Per Acre" for agronomic evaluation.
Key Factors That Affect Corn Yield Results
Several variables impact the final figures when calculating corn yield by weight:
Moisture Shrink: This is the invisible loss. As corn dries, it loses weight. Commercial elevators often apply a "shrink factor" (e.g., 1.4%) that is slightly higher than the mathematical water loss to account for handling losses (dust, fines).
Test Weight: While 56 lbs is the standard, corn with low test weight (e.g., 52 lbs/bu) may take up more volume for the same weight, but yield is sold by weight. High test weight corn is generally higher quality but sold on the same 56lb basis.
Foreign Material (FM): Trash, cob pieces, and stalks add weight but not value. Calculating corn yield by weight accurately requires deducting the percentage of FM before applying moisture formulas.
Scale Accuracy: A non-certified scale can introduce errors of 1-5%, drastically altering the yield data.
Field Variability: Calculating yield for a whole field averages out high and low spots. Precision agriculture relies on segmented weight checks.
Drying Costs: While not part of the physical yield, the cost to remove moisture affects the "net financial yield." Higher moisture means lower net profit per bushel.
Frequently Asked Questions (FAQ)
1. Why is 56 lbs used as the divisor?
56 lbs is the USDA standard weight for one bushel of shelled corn at 15.5% moisture. It provides a standardized unit for trade.
2. Does this calculator account for commercial shrink fees?
This tool uses the mathematical dry matter formula. Commercial elevators often use a shrink factor (e.g., 1.4% per point) which calculates slightly lower yields to cover their handling losses.
3. Can I use this for ear corn?
No. Ear corn (corn on the cob) has a standard bushel weight of 70 lbs. This tool for calculating corn yield by weight is for shelled corn only.
4. How accurate is calculating corn yield by weight compared to yield monitors?
Weight-based calculation is the "gold standard." Yield monitors must be calibrated against actual scale weights to be accurate.
5. What if my corn is below 15.5% moisture?
You effectively sell "extra" dry matter. While you don't get a bonus for 14% corn usually, the weight is not discounted. Some contracts allow for shrinkage reversal, but most do not.
6. How do I calculate yield if I only have volume (bin measurements)?
You would need a bin volume calculator. Calculating corn yield by weight requires a scale ticket.
7. Why is my yield lower than expected?
High moisture at harvest is the most common reason. Harvesting at 25% moisture reduces marketable weight by over 11% compared to the wet weight.
8. Is calculating corn yield by weight necessary for crop insurance?
Yes. Adjusters require scale tickets and moisture sheets to prove the actual production history (APH).