Concrete Volume Calculator
A general-purpose concrete calculator for any rectangular pour, solid cylinder or hollow ring such as a well or manhole liner. Enter the dimensions in one unit and get the volume in cubic metres, cubic feet and cubic yards, with premix bags and cement for a site mix.
Calculate concrete volume
Concrete volume formulas
Rectangle or block
V = L × W × DSlabs, footings, walls, kerbs and steps broken into blocks.
Solid cylinder
V = π × (d ÷ 2)² × hRound columns, piers, post holes and sonotubes.
Hollow cylinder (ring)
V = π ÷ 4 × (D² − d²) × hD = outer diameter, d = inner diameter. Used for well rings, manhole risers, round planters and tank walls.
All three are multiplied by the quantity and then increased by your waste allowance. Premix bags use a yield of about 2,135 kg per cubic metre; site-mix cement uses a 1 : 2 : 4 mix with a 1.54 dry-volume factor.
Worked examples
- V = 2 × 1.5 × 0.2 = 0.60 m³
- +5% waste = 0.63 m³ = 22.2 ft³ = 0.82 yd³
- Premix = 0.63 × 2,135 ÷ 25 = 54 × 25 kg bags
- V = 0.7854 × (1.2² − 1.0²) × 0.5 = 0.7854 × 0.44 × 0.5 = 0.173 m³
Concrete volume conversions
| From | To | Multiply by |
|---|---|---|
| Cubic metres (m³) | Cubic yards (yd³) | 1.30795 |
| Cubic yards (yd³) | Cubic metres (m³) | 0.764555 |
| Cubic metres (m³) | Cubic feet (ft³) | 35.3147 |
| Cubic yards (yd³) | Cubic feet (ft³) | 27 |
| Cubic metres (m³) | Litres | 1,000 |
| Cubic metres of concrete | Weight (approx.) | 2,400 kg (4,050 lb per yd³) |
How to use the calculator
- Pick metric or imperial. All three dimensions are entered in the same unit (metres or feet).
- Pick a shape and fill in the fields it needs. For a ring, put the outer diameter in the first field and the inner diameter in the second.
- Convert thin dimensions. A 15 cm depth is 0.15 m; a 4 in depth is 0.333 ft.
- Calculate. For L-shapes or complex pours, run each part separately and add them.
Frequently asked questions
How do I calculate the volume of concrete?
Multiply length × width × depth for rectangular shapes, or π × radius² × height for round ones, with all measurements in the same unit. The answer is in cubic metres or cubic feet.
How many cubic feet are in a yard of concrete?
One cubic yard equals 27 cubic feet (3 ft × 3 ft × 3 ft), or 0.765 m³.
How much does a cubic metre of concrete weigh?
Normal reinforced concrete weighs about 2,400 kg per cubic metre, or roughly 4,050 lb per cubic yard.
Related calculators
Results are estimates for planning and ordering. Verify dimensions on site before buying materials.