Compost Calculator

A compost or mulch calculator determines how many litres or bags are needed to cover a garden area at a target depth. Compost improves soil structure, moisture retention, and microbial life

The calculator uses the standard published formula for compost or mulch. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

This calculator works with centimetres, inches, litres, percentages. You can enter values in the units shown — the calculator handles all conversions internally.

The core formula is: Volume = Length × Width × Depth (all metres). Each step in the calculation is shown so you can verify the result manually.