Calculator
Choose a shape, enter dimensions and fill depth, then calculate adjusted soil volume.
Example data table
| Bed type |
Dimensions |
Fill depth |
Beds |
Settling |
Adjusted volume |
| Rectangular |
8 × 4 (ft) |
12 (in) |
1 |
10% |
~2.17 cu yd |
| Rectangular |
2.4 × 1.2 (m) |
30 (cm) |
2 |
8% |
~1.87 m³ |
| Circular |
6 (ft) diameter |
10 (in) |
1 |
12% |
~0.65 cu yd |
Examples are rounded for quick planning.
Formula used
First calculate bed area, then multiply by fill depth, then apply settling.
- Area (rect) = Length × Width
- Area (circle) = π × (Diameter ÷ 2)²
- Area (oval) = π × (Major ÷ 2) × (Minor ÷ 2)
- Area (triangle) = 0.5 × Base × Height
- Volume = Area × Depth
- Adjusted volume = Volume × (1 + Settling% ÷ 100)
How to use this calculator
- Select a unit system that matches your tape measure.
- Pick the bed shape and enter the required dimensions.
- Enter the soil fill depth you actually plan to add.
- Set the number of identical beds to scale totals.
- Add a settling allowance so your bed stays full.
- Optionally enter bag or bulk rates to estimate costs.
- Press Calculate to see results above this form.
- Download CSV or PDF for purchasing and records.