About the Concrete Column Calculator
Concrete for round or rectangular columns and piers, with formwork area and rebar estimate.
Also known as: column concrete volume, pier concrete, post hole concrete, pillar concrete.
How to use this calculator
- Enter shape, height, number of columns, mix ratio and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
Volume = cross-sectional area × height × number of columns
Worked example
Using the values pre-filled in the calculator above:
- Shape: Rectangular
- Width = 0.3 m
- Depth = 0.3 m
- Height = 3 m
- Number of columns = 4
- Mix ratio: 1 : 1 : 2 (M25) — 25 MPa — columns and beams
the calculator returns:
- Concrete required: 1.134 m³
- Per column: 0.27 m³
- Cement bags (50 kg): 13
- Formwork area: 14.4 m²