Compost C:N Ratio Calculator
Calculate carbon to nitrogen ratio for composting
About this calculator
The Compost C:N Ratio Calculator helps gardeners and composters determine the optimal carbon to nitrogen balance in their compost pile. A proper C:N ratio (ideally 25-30:1) ensures efficient decomposition, prevents odors, and produces nutrient-rich compost. By calculating the ratio of your brown materials (carbon-rich) to green materials (nitrogen-rich), you can adjust your compost mix for faster breakdown and better results.
How to use
Enter the amounts of your carbon-rich materials (browns like dried leaves, paper, cardboard) and nitrogen-rich materials (greens like kitchen scraps, grass clippings). The calculator will compute your current C:N ratio and indicate whether you need to add more browns or greens to achieve the optimal composting balance.
Frequently asked questions
What is the ideal C:N ratio for composting?
The ideal carbon to nitrogen ratio for composting is between 25:1 and 30:1, which promotes efficient decomposition and prevents odors.
What happens if my C:N ratio is too high?
A high C:N ratio (too much carbon) slows decomposition. Add nitrogen-rich greens like kitchen scraps or grass clippings to balance it.
What are common carbon and nitrogen sources for compost?
Carbon sources include dried leaves, paper, and cardboard. Nitrogen sources include kitchen scraps, fresh grass clippings, and coffee grounds.