Topsoil Calculator: measuring notes and method
Measure the new soil layer
Use the intended additional depth, not the whole depth of an existing bed. Divide changing fill depths into sections and exclude paths or areas receiving a different material.
Confirm delivery units
Use the volume result for a cubic-metre order. For a weight-based quote, include the density you used so the supplier can check the conversion.
Formula
Volume = length × width × depth × (1 + waste ÷ 100). Mass = volume × density.
Worked examples in metric and imperial units
Illustrative values match Reset example and stay fixed when you edit the calculator. Both columns describe the same calculation; converted inputs are rounded.
Metric worked example
- Length
- 6 m
- Width
- 4 m
- Finished depth
- 100 mm
- Bulk density
- 1,400 kg/m³
- Waste allowance
- 10 %
Material weight: 3,696 kg
Imperial worked example
- Length
- 19.685 ft
- Width
- 13.1234 ft
- Finished depth
- 3.937 in
- Bulk density
- 87.3991 lb/ft³
- Waste allowance
- 10 %
Material weight: 8,148.2852 lb
Follow the calculation
Lengths in this working are in metres.
- Net volume = 6 × 4 × 0.1 = 2.4 m³.
- Allowance multiplier = 1 + 10 ÷ 100 = 1.1.
- Mass = 2.64 m³ × 1,400 kg/m³ = 3,696 kg.
Unit conversions
1 m³ = 1,000 L ≈ 1.30795 yd³. One cubic yard is 27 ft³.
For metric tonnes, divide kg by 1,000. For US short tons, divide lb by 2,000; a long ton is 2,240 lb. Confirm your supplier’s unit.
Reviewed 19 October 2026. How calculations are checked · Report a correction