Volume Calculator
Calculate cylindrical tank volume in liters or cubic meters using radius and height
Height Calculator
Calculate cylindrical tank height from volume and radius in millimeters or meters
Weight Calculator
Calculate the weight of liquid in cylindrical tanks using volume and material density
Diameter Calculator
Calculate cylindrical tank diameter and radius from volume and height
Cylindrical Tank Volume Calculator
Calculate cylindrical tank volume in liters or cubic meters using radius and height.
Height
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Radius
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Diameter
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Volume
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Not to scale · updates live
Result
Enter radius (or diameter) and height to see the result.
How to calculate the volume of a cylindrical tank
You need two measurements, the width across and the height, both in the same unit.
- 01
Pick the unit you measured in
The dropdown covers mm (the default), cm, m, km, inches, feet and yards. Radius, diameter and height all use the same unit, so measure everything the same way.
- 02
Enter the inside radius or diameter
Fill in either one and the other updates itself. Measure inside the wall if you can. Outside measurements include the wall thickness and overstate how much the tank holds.
- 03
Enter the height and read the capacity
The result shows litres and cubic metres, worked out with V = π × r² × h. A tank 1 m across and 1.5 m tall holds 1,178 L, or 1.18 m³.
Capacity of common tank sizes
Use this to sanity-check a brochure or a result. Each cell is π × (diameter ÷ 2)² × height, converted to litres and rounded to the nearest litre.
| Inside diameter | 1.0 m tall | 1.5 m tall | 2.0 m tall |
|---|---|---|---|
| 0.6 m | 283 L | 424 L | 565 L |
| 0.8 m | 503 L | 754 L | 1,005 L |
| 1.0 m | 785 L | 1,178 L | 1,571 L |
| 1.2 m | 1,131 L | 1,696 L | 2,262 L |
| 1.5 m | 1,767 L | 2,651 L | 3,534 L |
| 2.0 m | 3,142 L | 4,712 L | 6,283 L |
Notice how diameter dominates. Going from 1.0 m to 2.0 m across quadruples the capacity at any height, because the radius is squared. Adding height only grows it in a straight line.
Two worked examples
A standard steel drum is about 572 mm across inside and 851 mm tall. Enter 572 as the diameter and 851 as the height in mm, and you get 218.68 L. That's why a drum sold as "200 litres" or "55 gallons" holds a little more than its label when filled to the brim.
Pipes work the same way, lying down. 100 m of pipe with a 50 mm bore holds π × 0.025² × 100 = 0.196 m³, or 196 L of water. Enter the length as the height. It's a useful figure when you're draining a system or dosing it with antifreeze.
Where cylinder volume comes up
Rooftop and underground water tanks
Check whether the tank you've got matches what the dealer said it holds, before you plan water use around it.
Rain barrels and harvesting drums
Measure a drum you already own to see how many litres one good downpour can fill.
Concrete columns and sonotubes
A round column 300 mm across and 3 m tall needs 0.21 m³ of concrete. Order a little extra for waste.
Draining a heating loop
Measure the pipe runs and add them up, so you know how much water or glycol will come out and go back in.
What the volume calculator assumes
- It treats the tank as a straight cylinder with flat ends. Domed or cone-bottom tanks hold a bit more or less, so add the end sections separately.
- It gives full capacity only. For a horizontal tank part-filled to a certain depth, the maths is different and this tool won't do it.
- Results are in litres and cubic metres. For US gallons, divide litres by 3.785 or use the Volume Converter: 1,178 L is 311.2 gallons.
- Answers are rounded to two decimal places, with very small cubic-metre values shown to four.