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Calcimator

Compost Ratio Calculator

Calculate your compost C:N ratio from green and brown materials. Get quality assessment and adjustment suggestions for optimal decomposition.

Inputs

cu ft
cu ft

Results

C:N Ratio

48.8:1

Quality AssessmentToo Much Carbon
Adjustment SuggestionAdd more green material. Try adding 30 cu ft of green material to reach a 30:1 ratio.
Total Material Volume20 cu ft
Green:Brown Volume Ratio0.33:1
Est. Finished Compost8 cu ft
Est. Decomposition Time24 weeks

C:N Ratio

48.8:1

How to Use This Calculator
  1. Start by filling in the input fields below. Results update instantly as you type, so you can experiment with different values to see how they affect the outcome.
  2. Green Material Volume — Volume of nitrogen-rich green materials in cubic feet. Accepts values from 0.5 cu ft to 500 cu ft (default: 5 cu ft).
  3. Green Material Type — Primary type of green (nitrogen-rich) material being composted. Choose from: Grass Clippings (C:N ~15:1), Fruit & Veggie Scraps (C:N ~25:1), Coffee Grounds (C:N ~6:1), Fresh Manure (C:N ~12:1), Garden Weeds (C:N ~20:1). default: 1.
  4. Brown Material Volume — Volume of carbon-rich brown materials in cubic feet. Accepts values from 0.5 cu ft to 500 cu ft (default: 15 cu ft).
  5. Brown Material Type — Primary type of brown (carbon-rich) material being composted. Choose from: Dry Leaves (C:N ~60:1), Straw (C:N ~80:1), Sawdust (C:N ~400:1), Cardboard (C:N ~170:1), Wood Chips (C:N ~70:1). default: 1.
  6. Once all inputs are set, review your results in the Results panel. Here's what each output means:
  7. C:N Ratio — shown as a numeric value. This is the primary result of this calculator.
  8. Quality Assessment — your calculated result.
  9. Adjustment Suggestion — your calculated result.
  10. Total Material Volume — shown as a numeric value.
  11. Green:Brown Volume Ratio — shown as a numeric value.
  12. Est. Finished Compost — shown as a numeric value.
  13. Est. Decomposition Time — shown as a numeric value.
  14. Explore the related calculators below if you need deeper analysis or want to approach this topic from a different angle.
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