Concrete Column Calculator

Volume and bags of concrete for round columns or tube footings.

Concrete volume 0.256
Concrete volume 6.912
80 lb bags (bags) 12

Formula: volume = π × (diameter/2)² × height × quantity

Step-by-step with your numbers:
1. Values used:
2. Diameter = 12
3. Height = 8
4. Number of columns = 1
5. Waste = 10 %
6.
7. Concrete volume = 0.256
8. Concrete volume = 6.912
9. 80 lb bags = 12bags
Did we solve your problem today?

Find the concrete needed to fill round columns, piers or cardboard tube forms (Sonotubes).

The math behind it

A column is a cylinder: volume = π × radius² × height. The diameter (inches) is halved and converted to feet.

Multiply by the number of columns and add waste; convert to cubic yards (÷27) or bags.

Worked example

One 12 in × 8 ft column → π × 0.5² × 8 = 6.28 ft³ (≈11 × 80 lb bags with waste).

FAQ

What is a Sonotube?

A waxed cardboard tube used as a one-time form to pour round concrete columns and footings.