Concrete Calculator
Work out how much concrete you need for a slab, base or footing.
Concrete required
1.2m³
- Cubic feet
- 42.4 ft³
- Cubic yards
- 1.57 yd³
Order a little extra to allow for spillage and uneven sub-base.
v1.0 · Reviewed September 2026
How this is worked out
Volume is length × width × depth, with the depth converted from millimetres to metres. The cubic feet and cubic yards figures are the same volume converted using 1 m³ = 35.3147 ft³ and 1 m³ = 1.30795 yd³.
Worked example
- Length 4 m
- Width 3 m
- Depth 100 mm
4 × 3 × 0.1 = 1.2 m³
1.2 m³, which is 42.4 ft³ or 1.57 yd³
Assumptions and limits
- The pour is a plain rectangle at a constant depth, so steps, thickenings and haunching are not included.
- No waste allowance is added, so order a little over the calculated volume.