cylinder volume calculator
Calculate a cylinder's volume in cubic feet, cubic yards, gallons, and liters from diameter and height — for tanks, pipes, and round columns.
A cylinder’s volume comes up constantly in construction — round concrete columns, pipe segments, drums, and tanks. Enter the diameter and height and get the volume in cubic feet, cubic yards, gallons, and liters.
How this calculator works
Cylinder volume is pi times the radius squared, times the height. Radius is half the diameter.
Formula: Cubic feet = π × (diameter ÷ 2)² × height. Cubic yards = ft³ ÷ 27. Gallons = ft³ × 7.48052. Liters = ft³ × 28.3168.
Worked example
A cylinder 4 ft in diameter and 6 ft tall:
- Radius: 4 ÷ 2 = 2 ft
- Cubic feet: π × 2² × 6 ≈ 75.40 ft³
- Cubic yards: 75.40 ÷ 27 ≈ 2.793 yd³
- Gallons: 75.40 × 7.48052 ≈ 564.0 gal
- Liters: 75.40 × 28.3168 ≈ 2135.0 L
Reference
| Diameter × Height (ft) | Cubic feet |
|---|---|
| 2 × 4 | 12.57 ft³ |
| 4 × 6 | 75.40 ft³ |
| 6 × 10 | 282.74 ft³ |
How to measure
Measure diameter across the widest point of the circular face, and height (or length, if it’s lying on its side) along the axis. This applies directly to sonotube footings, round concrete columns, drainage pipe segments, and cylindrical water tanks. For a rectangular space instead, use the Volume Calculator.
Frequently asked questions
What's the formula for cylinder volume?
Volume equals pi times the radius squared times the height: V = π × r² × h. The radius is half the diameter, so enter diameter and the calculator halves it automatically.
Why does the calculator ask for diameter instead of radius?
Diameter is what you'd actually measure with a tape across a pipe, tank, or post — it's the easier field measurement. The calculator divides by 2 internally to get the radius the formula needs.
How do I find the volume of a concrete column or footing?
Measure the column's diameter and its height (or depth, for a vertical footing like a sonotube), enter both here, and the cubic feet result converts directly to cubic yards for a concrete order.
How does this differ from a cone or a tank calculator?
A cylinder has the same diameter top to bottom, like a pipe or drum. A cone tapers to a point. A tank calculator often adds capacity-specific extras like fill percentage — for a straight cylindrical tank the math here is identical.
What if my cylinder is lying on its side, like a horizontal tank?
The total volume is the same regardless of orientation — π × r² × length still applies, using the tank's length in place of height. Note that a horizontal tank isn't full at every fill height, so use this for total capacity, not partial fill.
How accurate is pi in this calculation?
The calculator uses a full-precision value of pi (3.14159...), so the only error comes from how precisely you measure diameter and height.
Estimates only. Verify quantities with your supplier before purchasing.