THE MATERIALS DESK / COMPOST
Compost calculator.
Plan a compost layer or top-up using your own application depth. Calculate volume, whole bags, and a clear project total.
YOUR GARDEN, IN PERSPECTIVE8 ft × 4 ft · 1 in deep
COMPOST VOLUME TO PLAN FOR
2.67cu ft
0.1 cu yd · 76 L
2 bagsat 1.5 cubic feet each
Rounded up8 × 4 × (1 ÷ 12) = 2.67 cubic feet.
Saved on this device. No account needed.
Small layers still deserve careful measurements.
How to measure your bed ↗A worked example
A 12 × 4 ft bed with a 1-inch application needs 4 cu ft of compost. At 1.5 cu ft per bag, round 2.67 up to 3 bags.
This tool estimates volume, not nutrient needs. Compost suitability and application depth depend on your soil, plants and product. Use local guidance or soil-test advice for those decisions.
The calculator converts your measurements, applies your optional allowance, and rounds the final bag quantity up. It does not assume a density or predict settling.
Before you place the order
- Use inside dimensions and only the layer that will contain this material.
- Check the net volume printed on the bag. Weight alone cannot tell you volume without a material-specific density.
- Confirm delivery minimums and ordering increments with the supplier.
- Group matching products before rounding a combined order; different materials stay separate.