Compost Carbon:Nitrogen Ratio Calculator

Estimate the combined carbon-to-nitrogen ratio of two compost ingredients from their dry-matter proportions and C:N ratios.

How it works

Each ingredient ratio is converted into relative carbon and nitrogen fractions, those fractions are combined by the entered dry-matter parts, and total carbon is divided by total nitrogen.

combined C:N = total carbon ÷ total nitrogen

Limitations

  • This is an approximate dry-matter calculation. Real feedstocks vary in moisture, composition and measured C:N ratio.