Vertical cylinder and rectangular
A vertical cylinder holds π × r² × h; a rectangular tank holds length × width × height. For the liquid volume, use the liquid level instead of h.
Free industrial tool
Tank Volume Calculator
Enter the dimensions and liquid level to get the total and filled volume of your tank in liters, cubic meters and gallons.
Result
Enter the tank dimensions.
Total volume
– liters
Liquid volume
– liters
Empty space
– liters
Fill level
Calculated for flat-ended tanks. For dished or conical heads, add the head volume separately.
Formulas
How is tank volume calculated?
Horizontal cylinder
In a horizontal tank the liquid cross-section is a circular segment, so volume is not linear with level. Segment area × tank length gives the exact volume.
Spherical tank
A sphere holds (4/3) × π × r³. The liquid volume at level h comes from the spherical cap formula: π × h² × (3r − h) / 3.
Tips for accurate measurement
- Measure the inner diameter — wall thickness makes a difference of hundreds of liters on big tanks.
- Use the same unit for every dimension; the tool converts the result to liters and m³ for you.
- For custody transfer and fuel sales, use a certified strapping (calibration) table.
- For continuous monitoring, install a radar or ultrasonic level sensor instead of a dipstick.
FAQ
Tank volume questions
How do I calculate the volume of a cylindrical tank?
Square the radius (half the diameter), multiply by 3.1416, then by the height. With dimensions in meters the result is in m³; multiply by 1000 for liters.
How many liters are in a cubic meter?
One cubic meter is 1000 liters, or about 264.2 US gallons.
Why is a horizontal tank not linear with level?
The liquid surface is widest in the middle and narrowest at the bottom and top. Half the height is 50% of the volume, but 25% of the height is only about 19.6%.
How do I account for dished heads?
This tool assumes flat ends. For 2:1 ellipsoidal heads each head adds roughly π × D³ / 24, which you add to the shell volume.
How can I measure tank level automatically?
Radar level sensors such as VEGAPULS measure the level without touching the liquid and, with a volume table, show the liters in the tank in real time.
Measure tank level automatically and precisely
Bizdavar supplies VEGA level and pressure sensors for water, fuel and chemical tanks and helps you choose the right model.