About the Compost Calculator
Compost needed for beds and borders, and how much your kitchen waste will make.
Also known as: compost quantity calculator, how much compost, compost bin calculator, garden compost volume.
How to use this calculator
- Enter calculate and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
volume = area × depth · compost yield ≈ 30% of raw waste by weight
Worked example
Using the values pre-filled in the calculator above:
- Calculate: Compost needed
- Area = 30 m²
- Depth to apply = 50 mm
the calculator returns:
- Compost needed: 1.5 m³
- In litres: 1,500
- 50 litre bags: 30
- Weight: 1,050 kg