Concrete Column Calculator
Calculate concrete volume for cylindrical columns, piers, and support posts.
Formula & Explanation
A cylindrical column volume is calculated using: Volume (cu ft) = π × r² × h Where: - r is the radius in feet (diameter ÷ 2, converted from inches) - h is the height in feet - π ≈ 3.14159 The diameter is entered in inches and converted to feet by dividing by 12, then halved to get the radius. To convert cubic feet to cubic yards, divide by 27. Final bags = ceil(Volume × (1 + Waste%) ÷ Bag Yield)
Assumptions
- •The column is perfectly cylindrical with uniform diameter
- •Diameter is entered in inches; height in feet
- •The formula assumes a solid column (not hollow)
- •Bag yield values are industry standards-confirm with your product
- •A 10% waste allowance is typical for cylindrical forms
Example Calculation
A cylindrical column 12 inches in diameter and 10 feet tall requires approximately 7.85 cubic feet of concrete. With 10% waste and 60 lb bags, you need 20 bags.
Inputs
Results
Common Column Sizes & Concrete Volume
| diameter_in | height_ft | volume_cuft | volume_cuyd | bags_60lb |
|---|---|---|---|---|
| 8" | 8 ft | 3.49 | 0.13 | 9 |
| 12" | 10 ft | 7.85 | 0.29 | 20 |
| 12" | 12 ft | 9.42 | 0.35 | 24 |
| 18" | 12 ft | 21.21 | 0.79 | 53 |
| 24" | 12 ft | 37.7 | 1.40 | 94 |
Frequently Asked Questions
Related Calculators
Concrete Footing Calculator
Calculate concrete volume and bag requirements for fence posts, deck footings, and pier foundations.
Concrete Slab Calculator
Calculate concrete volume and bag requirements for rectangular slabs, patios, and floor pours.
Concrete Wall Calculator
Calculate concrete volume for concrete walls, retaining walls, and foundation walls.
Concrete Bag Calculator
Calculate how many bags of concrete are needed for a given volume.