Tank Volume Calculator
Work out the volume of a vertical cylindrical tank in both cubic metres and litres, with an optional liquid level so you can also read off how much is currently held. Handy for water tanks, fuel tanks, and process vessels.
Enter Values
How to use this calculator
- Enter the tank's internal diameter in metres.
- Enter the tank's full height in metres.
- Optionally enter the current liquid level to get the filled volume as well; leave it blank for the full-tank capacity only.
How it works
The tank is modelled as a vertical cylinder. The radius r is half the diameter, and the full volume is the circular cross-section area times the tank height: V = π·r²·H. If a liquid level is given, the filled volume uses the same cross-section over the level height: π·r²·level. Volumes are converted to litres using 1 m³ = 1,000 L.
Worked example
Worked example. A tank 3 m across and 5 m tall has a radius of 1.5 m and a full volume of π·1.5²·5 = 35.34 m³ (35,342.92 L). Filled to a 2 m level it holds π·1.5²·2 = 14.14 m³ (14,137.17 L).
Common mistakes
- Entering the radius in the diameter field — use the full internal diameter.
- Entering a liquid level greater than the tank height, which is rejected as invalid.
- Applying this to a horizontal or cone-bottomed tank, whose geometry differs from a vertical cylinder.
Frequently asked questions
Does it work for horizontal tanks?
No — it assumes a vertical cylinder. Horizontal cylinders and coned-base tanks need different formulas for partial fill.
How are litres calculated?
One cubic metre equals 1,000 litres, so the tool multiplies the cubic-metre result by 1,000.
Related tools
- Pit Volume from Dimensions Calculator
- Mound Volume Calculator
- Capsule Volume Calculator
- Sump Inflow Rate Calculator
- Irregular Stockpile Volume Estimator
- Bin and Hopper Volume Calculator
Explore more in Geometry, Shape, Area & Volume.
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.