Dry Matter Calculator
Convert an as-fed (wet) sample weight and moisture content into dry matter percentage and dry matter weight, a standard step in forage and feed analysis.
What Is Dry Matter?
Dry matter (DM) is the portion of a feed, forage, or plant sample that remains after all the water has been removed. Because feeds vary a lot in moisture content, expressing nutrient values or weights on a dry-matter basis lets farmers and nutritionists fairly compare different feeds, such as fresh-cut grass versus dried hay.
The Formula
Dry matter percentage is simply 100% minus the moisture percentage: DM% = 100 − Moisture%. The dry matter weight is then the as-fed (wet) weight multiplied by that percentage: Dry Matter Weight = As-Fed Weight × (DM% ÷ 100). The remaining weight is water.
Why It Matters
Ration formulation, hay pricing, and silage inventory all typically rely on dry-matter figures because feeding decisions based on wet weight alone can significantly under- or over-estimate the actual nutrients or dry material an animal receives. This calculator is intended for general agricultural planning and educational purposes; for precise feed analysis, use results from a certified forage testing laboratory.