TryBuildCalcCircular Column Concrete Calculator (Rectangular & Circular — Volume, Cement, Sand & Aggregate)
Calculate column concrete volume and materials.
Calculate concrete volume and materials for circular RCC columns under a single steel column or decorative/architectural use. Adjust column type, height, width/depth or diameter, count, mix ratio, and wastage for your RCC estimate.
🕒 Last updated: August 5, 2026
Inputs
ℹ️Rectangular/Square uses Height x Width x Depth. Circular uses the circle area (pi x (Diameter/2)^2) x Height — a genuinely different formula, not just a relabeled rectangle.
ℹ️Enter the diameter, not the radius — using the radius here would understate volume by a factor of 4.
Cost
Showing results for 4 columns
Concrete Volume
0.848 m³ / 29.9 cft
(0.212 m³ / 7.5 cft per column)
Total Wet Volume: 0.848 m³ / 29.9 cft
Dry Volume: 1.306 m³ / 46.1 cft
Sand: 0.356 m³ / 12.6 cft
Aggregate: 0.713 m³ / 25.2 cft
(Per column: Sand 0.089 m³ / 3.1 cft, Aggregate 0.178 m³ / 6.3 cft)
Cement Required
(Including 5% Wastage)
8 bags
(2 bags per column)
Extra (Wastage): 0.34 bags
Setting up column formwork for this pour? Column Formwork Process Guide →
Approximate results for planning only. Verify with a professional.
Looking for the verification checklist, reference tables, tips, or common mistakes?See the complete Concrete Column Calculator.
4 circular columns, 300 mm diameter x 3 m height
A circular column uses Volume = pi x (Diameter/2)^2 x Height — a genuinely different formula from a rectangular column, since it's based on the circle's area rather than width x depth. For 4 columns at 300 mm diameter and 3 m height, total wet volume is 0.848 m³, dry volume 1.306 m³, needing about 8 cement bags (1:1.5:3 mix, 5% wastage), 0.356 m³ sand, and 0.713 m³ aggregate.
The calculator is pre-filled for this column use case. Edit any input and the worked example updates from the active values.
- Default column: 300 mm diameter x 3 m height.
- Count: 4 columns.
- ~8 cement bags with 5% wastage (1:1.5:3 mix).
How does the concrete column calculator work?
Wet volume depends on the column shape — Rectangular/Square uses the cross-section area (Width × Depth), while Circular uses the circle area instead. Every shape then follows the same dry-volume, mix-ratio, and wastage steps.
Step 1 — Rectangular / Square
Step 2 — Circular
Enter the diameter, not the radius — the formula already halves it.
Step 3 — Convert to Dry Volume
The 1.54 factor accounts for voids in aggregates, sand bulking, and material loss during mixing.
Step 4 — Split by Mix Ratio
Step 5 — Convert Cement Volume to Bags
Step 6 — Add Wastage
Step 7 — Cost (Optional)
All three quantities are priced at their wastage-adjusted amount — the quantity you'd actually order, not the theoretical minimum before wastage. Sand and aggregate prices can be entered per m³ or per cft — whichever unit you enter is converted to match the volume automatically.
Worked Example
This example uses the active inputs above and follows the same steps as the Formula section.
Input Values Used
| Input | Value |
|---|---|
| Column Type | Circular Column |
| Height | 3 m (3 m) |
| Diameter | 300 mm (0.3 m) |
| Count | 4 |
| Concrete Mix | M20 (1:1.5:3) |
| Wastage | 5% |
Step 1 — Wet Volume
| Calculation | Substitution | Result |
|---|---|---|
| π × (D / 2)² × H × Count | π × (0.3 / 2)² × 3 × 4 | 0.848 m³ / 29.9 cft |
Step 2 — Dry Volume
| Calculation | Substitution | Result |
|---|---|---|
| Dry Volume = Wet Volume × 1.54 | 0.848 × 1.54 | 1.306 m³ / 46.1 cft |
Step 3 — Materials & Cement Bags
| Material | Share of Mix (1:1.5:3) | Result |
|---|---|---|
| Sand | 1.5 / 5.5 | 0.356 m³ / 12.6 cft |
| Aggregate | 3 / 5.5 | 0.713 m³ / 25.2 cft |
| Cement Bags (with 5% wastage) | 1 / 5.5 | 8 bags |
Therefore, this circular column needs approximately 0.848 m³ / 29.9 cft of concrete, requiring 8 cement bags, 0.356 m³ / 12.6 cft sand, and 0.713 m³ / 25.2 cft aggregate (including 5% wastage on cement).
Cross-check against the Column Type & Mix Reference table in the complete Concrete Column Calculator.