Vertical Cylindrical Tank Volume Calculator
Work out the volume and capacity of a vertical cylinder tank — one standing upright on its end — in US gallons, imperial gallons, litres, cubic feet and cubic metres. Enter the diameter and height for the total capacity, or turn on partial fill to find how much liquid is in a part-full tank.
Tank volume calculator
How to calculate vertical cylindrical tank volume
A vertical cylinder is the simplest cylindrical tank to work out. The volume of a cylindrical tank is the area of its circular base multiplied by its height:
where r is the inside radius and h is the height. If you know the diameter d rather than the radius, use r = d / 2, giving the same cylindrical tank volume formula written as V = π × (d / 2)² × h. This is also the capacity of a cylindrical tank: fill it to the brim and the capacity equals the volume.
Round and circular tank volume
A round tank or circular tank is usually a vertical cylindrical tank: the base is a circle, and the tank rises straight up from that circular footprint. That means this page can also be used as a round tank volume calculator or circular tank volume calculator when the tank has flat ends and a constant diameter from bottom to top. Enter the inside diameter and height to find the total capacity in gallons, litres, cubic feet and cubic metres.
Partial fill is linear for a vertical tank
The big advantage of an upright cylinder is that partial fill is proportional to height. Because every horizontal slice has the same circular area, the filled volume at a liquid height hf is just:
So a vertical tank filled to half its height holds exactly half its capacity; filled to a quarter of its height, a quarter of its capacity. This is unlike a horizontal cylinder, where the liquid forms a circular segment and depth and volume are not proportional — if your tank lies on its side, use the horizontal cylindrical tank volume calculator instead. For the derivations and sources behind every formula on this site, see the methodology page.
Worked example
Take a vertical cylinder tank with a diameter of 4 ft (so r = 2 ft) and a height of 6 ft.
- Total volume: V = π × 2² × 6 = 75.40 ft³. At 7.48052 US gallons per cubic foot, that is about 564 US gallons (≈ 470 imperial gallons, ≈ 2,135 litres).
- Half full (liquid height = 3 ft): V = π × 2² × 3 = 37.70 ft³ ≈ 282 US gallons — exactly half the total, because partial fill scales linearly with height.
- Quarter height (liquid height = 1.5 ft): V = π × 2² × 1.5 = 18.85 ft³ ≈ 141 US gallons, exactly a quarter of the full capacity.
Enter these numbers in the calculator above to confirm the figures and read off imperial gallons, litres, cubic feet and cubic metres at the same time.
Units and gallons
This vertical tank volume calculator in gallons also reports every other common unit at once: US gallons, imperial (UK) gallons, litres, cubic feet and cubic metres, plus optional petroleum barrels. One US liquid gallon is 231 cubic inches ≈ 3.785 litres, while one imperial gallon ≈ 4.546 litres, so both are shown to avoid ambiguity. Enter inside dimensions for the closest estimate of liquid capacity.
Other tank shapes
For a cylinder lying on its side, use the horizontal cylindrical tank volume calculator. For capsule, rectangular, oval, elliptical, cone-bottom and cone-top tanks, the main tank volume calculator handles every supported tank shape with full and partial-fill results.
Frequently asked questions
How do you calculate the volume of a vertical cylindrical tank?
Use V = π × r² × h, where r is the inside radius (half the diameter) and h is the height of the cylinder. Multiply the circular base area, π × r², by the height. The calculator above does this from the diameter and height you enter and shows the result in US gallons, imperial gallons, litres, cubic feet and cubic metres at once.
What is the formula for the capacity of a cylindrical tank?
The capacity of a cylindrical tank is V = π × r² × h. If you know the diameter d instead of the radius, use r = d / 2, so V = π × (d / 2)² × h. Keep all dimensions in the same unit, then convert the result to gallons or litres — or let the calculator convert for you.
How do I find the volume of a partially filled vertical cylinder?
For a vertical (upright) cylinder, partial fill is linear: the filled volume is simply V = π × r² × (liquid height). Fill it to half the height and it holds exactly half its capacity. Turn on “Calculate partial fill”, enter the liquid level measured from the bottom, and the calculator reports the filled and empty volumes.
Does it matter whether the cylinder is vertical or horizontal?
For total capacity, no — V = πr²L is the same either way. For partial fill, yes. A vertical cylinder fills evenly with height, so the math is a simple proportion. A horizontal cylinder fills as a circular segment and is not proportional to depth. If your tank lies on its side, use the horizontal cylindrical tank volume calculator instead.
What units does this cylindrical tank calculator output?
Results appear simultaneously in US gallons, imperial (UK) gallons, litres, cubic feet and cubic metres, with an option to show petroleum barrels. One US liquid gallon is 231 cubic inches ≈ 3.785 litres; one imperial gallon ≈ 4.546 litres. Enter dimensions in US units (feet and inches) or metric (metres and centimetres) using the toggle.
Does the calculator include the tank’s domed top or bottom?
No. This page models a plain vertical cylinder with flat ends. Tanks with conical or dished bottoms hold a little differently — for a cone-bottom or cone-top tank, use the matching shape on the main tank volume calculator.
Can I use this as a round tank or circular tank capacity calculator?
Yes. If your round or circular tank is an upright cylinder with flat ends and the same diameter from bottom to top, use the vertical cylindrical tank formula: V = π × r² × h. Enter the inside diameter and height, and the calculator will estimate the round tank capacity in US gallons, imperial gallons, litres, cubic feet and cubic metres. If the tank lies on its side, use the horizontal cylindrical tank volume calculator instead.