Estimate the penalty for grain below standard test weight.
Enter your actual test weight, the standard (No. 1) test weight, the number of bushels, and the dollar-per-bushel deduction. The calculator shows how far below standard you are, the percentage discount, bushels deducted, and total dollar deduction.
A corn load tested 53 lb/bu instead of 56. The elevator took a 5% grade discount. On 5,000 bu that is 250 bu — about $1,100 lost to a combination of high moisture and delayed harvest that pushed test weight down.
✓ Expert Reviewed: This calculator and its content have been reviewed by agricultural experts. Formulas are based on standard extension service recommendations. For site-specific advice, consult your local agronomist.
Enter the required input values in the form fields above. Each field includes default values that you can adjust to match your specific situation. Click the Calculate button (or simply change any input) to see instant results. Use the Metric/Imperial toggle to switch between unit systems. Results are displayed in the results panel and can be used for farm planning and decision-making.
This calculator is designed to help farmers, agronomists, and agricultural students make quick, accurate calculations for farm management. It uses standard agricultural formulas based on extension service recommendations and scientific literature. Whether you are planning inputs, estimating yields, or managing finances, this tool provides reliable estimates to support your decisions.
Deficit = standard test weight − actual test weight (lb/bu). Discount % = deficit ÷ standard test weight. Bushels deducted = delivered bushels × discount %. Dollar deduction = bushels deducted × deduction rate per bushel. Typical standards: corn No. 1 = 56 lb/bu, No. 2 = 54, No. 3 = 52.
53 lb/bu actual vs 56 standard on 5,000 bu: deficit = 3 lb/bu, discount = 5.36%, bushels deducted = 268. At $0.30/bu: $80.40 deduction.
Common mistakes: comparing to the wrong standard (commodity-specific); using a flat 0.5 lb step when the proportional formula is more accurate; forgetting that low test weight also correlates with high moisture; not re-testing after drying.
USDA No. 2 corn requires 54 lb/bu minimum; No. 1 is 56 lb/bu. Each 2 lb drop is a grade. Below 52 lb/bu grain is No. 3 or lower and faces steep discounts.
Often, yes. As grain dries it settles and kernels pack more densely, raising test weight by 0.5–2 lb/bu. Re-test after drying before selling.
Lower test weight means less grain density per volume. Elevators sell by weight, so a bushel that weighs less costs them storage, transport and handling. They pass that cost on via discounts.
Drought stress, frost before maturity, high nitrogen with low stand, thin kernel filling, and harvesting too early. It is a quality signal, not just a number.
Compare storage costs and market price with the discount. Sometimes paying the discount and selling now beats storing, drying, and risking further quality loss.