Concrete Volume Calculator
Enter length, width and thickness to get the concrete volume you need and how many truck loads that is.
Inputs
Result
Formula
| Volume | V = length × width × thickness |
| With waste | V_total = V × (1 + waste %) |
| Truck loads | N = ceil(V_total ÷ truck capacity) |
A 6 m × 4 m × 0.15 m slab: V = 3.6 m³, 3.78 m³ with 5% waste, one 9 m³ truck load.
Concrete grades, typical uses and material reference
| Grade | Typical use | Cement (kg/m³) | Sand (m³/m³) | Gravel (m³/m³) |
|---|---|---|---|---|
| C15 | Blinding, plain footings | 260 | 0.55 | 0.88 |
| C20 | Floors, retaining walls, ordinary footings | 290 | 0.52 | 0.86 |
| C25 | Beams, slabs, columns, ring beams | 320 | 0.48 | 0.85 |
| C30 | Load-bearing structures, most common | 360 | 0.45 | 0.83 |
| C35 | High-rise columns, bridges, precast | 400 | 0.42 | 0.81 |
| C40 | Prestressed and long-span structures | 440 | 0.40 | 0.79 |
Quick volume for common members
| Member | Formula | Example |
|---|---|---|
| Rectangular slab | length × width × thickness | 6 × 4 × 0.15 = 3.6 m³ |
| Rectangular beam | width × depth × clear span | 0.3 × 0.6 × 5 = 0.9 m³ |
| Rectangular column | section L × section W × height | 0.5 × 0.5 × 3 = 0.75 m³ |
| Round column | 3.1416 × radius² × height | 3.1416 × 0.25² × 3 = 0.59 m³ |
| Strip footing | width × depth × length | 1.2 × 0.3 × 50 = 18 m³ |
FAQ
Why add a waste allowance to concrete volume?
Real pours lose material to spillage, over-excavation, formwork deflection and pump residue. Use 3-5% for slabs and beams, 5-10% for footings, irregular shapes or pumped concrete. Running short mid-pour creates a cold joint, which costs far more than the extra cubic metre.
How do cubic metres and cubic yards convert?
1 cubic yard = 0.7646 m³, so divide m³ by 0.7646 to order in yards. In China 1 方 is exactly 1 m³.
How do I handle columns and round footings?
Round column: V = π × r² × h. Tapered round footing: V = πh/3 × (R² + Rr + r²). This calculator uses a rectangular prism, so for a cylinder compute 3.1416 × radius² × height separately.
Related calculators
Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.