Harvest Loss Calculator
Free online tool to estimate combine seed loss from a field sample—see bu/ac loss, percent of yield, and dollar impact so you can tune the machine with confidence.
How the harvest loss calculator works
Use this combine harvest loss calculator after collecting seed behind the machine. Enter crop, cut width, discharge width, collecting area, and seed loss by weight (g), volume (mL), or seed count. The tool converts your sample into estimated loss per acre, percent of expected yield, and dollar value of that loss.
- Imperial or metric units
- Weight, volume, or count sampling methods
- Crop-specific conversion for realistic bu/ac results
- Optional combine adjustment walkthrough to reduce losses
Why measure harvest loss?
Even a small percent of seed left in the field adds up across acres. Checking combine seed loss during harvest helps you decide when to adjust rotor, shoe, or ground speed before losses get expensive.
Frequently asked questions
What does the Harvest Loss Calculator measure?
It estimates combine seed loss from a field sample and reports loss mass, volume (bu/ac), percent of expected yield, and dollar impact per acre.
Is this harvest loss calculator free?
Yes. The basic calculator on this page is free to use—no account required.
How do I check combine harvest loss in the field?
Collect seed from a known area behind the combine, record cut width and discharge width, then enter the numbers above. Compare the result to your expected yield and adjust the combine if loss is higher than your target.