Concrete Calculator
Calculate concrete volume for slabs, columns, and beams, and estimate the number of cement bags required.
Slab
ft
ft
ft
Result
Volume (ft³)
50.00
Volume (m³)
1.416
Cement Bags (50 kg)
10
What is a concrete calculator?
A concrete calculator estimates the volume of concrete you need for a slab, column, or beam, and approximates how many 50 kg cement bags that volume implies. It converts between cubic feet and cubic meters so you can order the right amount.
Formulas
Slab / Beam: V = length × width × depth
Column: V = π × (diameter/2)² × height
1 ft³ = 0.0283168 m³
Column: V = π × (diameter/2)² × height
1 ft³ = 0.0283168 m³
Example
A 10 ft × 10 ft slab at 0.5 ft depth needs 50 ft³ ≈ 1.42 m³ of concrete, or about 10 bags of 50 kg cement (≈ 7 bags per m³).
Common Use Cases
- Ordering concrete for a patio, driveway, or floor slab.
- Estimating material for columns and footings.
- Planning beams in small construction projects.
FAQs
How many cement bags per cubic meter?
This tool uses a rule-of-thumb of about 7 bags of 50 kg cement per cubic meter of concrete (a typical M20 mix). Actual usage varies with the mix design.
Should I add extra for waste?
Yes — add roughly 5–10% to the calculated volume to cover spillage, uneven subgrade, and formwork variations.