Concrete Calculator: Column (Rectangular / Circular) — Volume & Bags
Estimate concrete for prismatic columns. Choose rectangular or circular, enter section size, clear height, quantity, and waste allowance. Results include per-column volume and total with waste in m³, yd³, and ft³, plus approximate bag counts. Notes, formulas, and FAQs included.
Results
Per-column volume
0.000 m³
0.000 yd³
0.00 ft³
Cross-section area: 0.0000 m²
Total with waste
0.000 m³
0.000 yd³
0.00 ft³
Approximate bag counts (total with waste)
US bag sizes (QUIKRETE® yield)
Yields per bag from QUIKRETE data sheet. Actual yield varies with placement and compaction. Source
Metric bag sizes
Edit yields to match your local supplier data.
How to use this column calculator
- Select metric or US units.
- Choose the column shape (rectangular or circular).
- Enter section dimensions in mm or in and the clear height in m or ft.
- Set the number of identical columns and a waste allowance (many projects use 4–10%).
- Read per-column volume and total with waste, then review bag counts for ordering. Round up.
Formulas and assumptions
- Rectangular column: section area
A = B × D, volumeV = A × H. - Circular column: section area
A = π (Ø/2)², volumeV = A × H. - Total with waste:
Vtot,w = Veach × n × (1 + waste%). - Scope: Gross concrete only. Does not deduct steel volume, pockets, or block-outs, and does not size reinforcement or cover (design per your engineer / local code, e.g., ACI 318 or Eurocode 2).
References
- Concrete waste allowance ~4–10%: NRMCA Concrete In Practice CIP 8, CIP 31.
- US bag yields: QUIKRETE® Concrete Mix 1101 data sheet.
FAQs
Should I include capital/pedestal volumes?
If the column flares into a capital or sits on a pedestal poured monolithically, calculate those as separate prisms or cylinders and add to the result.
Do rebar and cages change the volume?
Steel displaces a small amount of concrete, usually negligible for ordering. If you need a net adjustment, subtract steel volume from the total.
What about tapered (frustum) columns?
This version assumes constant section. Ask for the tapered/frustum variant if needed.