Compost Calculator
Whether a compost pile is big enough to hold its own heat, and whether the carbon-to-nitrogen mix lands in the band that actually breaks down.
The pile
A pile smaller than about a cubic yard loses heat faster than it makes it. It will still compost — just slowly, and without getting hot enough to kill weed seeds.
What is going in
How it will behave
- Pile volume
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- Filled
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- Carbon to nitrogen
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- Browns : greens
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- Likely ready
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Add some material to the pile.
C:N is estimated from typical values by volume, not measured. Real material varies with moisture and how finely it is shredded, so treat 25–35 as the target band rather than 30 as a number to hit.