Proper calibration is important to get the most accurate measurements from your precision farming equipment. Documenting your calibration information will allow you to provide the correct data for Precision Claims. A producer must calibrate within 3% to meet the RMA calibration requirement.

  • Single-point: The last calibration needs to be within 3%. If a producer has been within 3% for the majority of harvest, and the last calibration is outside of the threshold, the producer will no longer qualify for a Precision Claim.

  • Multi-point: All calibration speeds need to be within 3%. At a minimum, five speeds must be recorded to qualify.

FMH Calibration Checklist

Use the FMH Calibration Report Form for multi-point combines or single-point combines to give you best practices and recommendations on calibration requirements, as well as a place to document your calibration records. Keep this in your equipment to record calibration adjustments.


During each yield monitor calibration, record the following:

  • Calibration Date and Time
  • Crop Harvested
  • Field Name – List the common field name (e.g., “Bob’s North 40”)
  • Scale Source – Source of the grain measurement (i.e., grain elevator, grain cart, etc.)
  • Machine Measured Weight – What is the combine showing for weight?
  • Scale Measured Weight – As measured by the scale source
  • Positive or Negative Weight Difference – Calculate the difference in weight
  • Current Calibration – Calibration factor on the precision ag equipment (i.e. GreenStar™ monitor) before entering the new weight
  • New Calibration – Calibration factor AFTER entering the new weight
  • Average Crop Moisture Percent - Average moisture for this load

Important Note: Maintain these records after harvest and provide them upon request to your FMH crop insurance provider.


  • Calibrate moisture sensors when harvest season is underway
  • Initially calibrate mass flow sensor at the beginning of the season for each crop, then calibrate as needed
  • Re-calibrate as crop conditions change significantly over the season (e.g., crop dry down, test weight, variety/hybrid change, crop field conditions change)
  • Calibration loads should be similar in size (3,000-6,000 lbs)
  • Use the same weight scales during calibration process
  • Before calibrating, be sure the grain tank and auger tube are completely empty. Be sure that the weigh wagon or truck hauling grain away from combine is also empty.