Concrete Tube Calculator

in
in
Enter 0 for solid cylinder.
ft

Calculate the volume of concrete needed to fill a hollow tubular form (annular ring cross-section).

Formula

Volume = π × (R_outer² − R_inner²) × height
  • For solid cylinder: set inner diameter to 0.
  • Convert height from ft to inches for calculation.

12 in OD, 0 inner, 4 ft tall (solid)

Inputs
  • Outer Diameter: 12 in
  • Inner Diameter (hollow): 0 in
  • Length / Height: 4 ft

π × 36 × 48 / 1728 ≈ 3.14 cu ft → 6 bags.

Frequently asked questions

When would I use a hollow tube?
For casting pipe pillars or decorative columns that will have a drainage pipe or conduit inside.