Rectangular container
Boxes, aquariums, straight-sided tanks, and rectangular pools.
Read the guide: How to calculate rectangular container volumeFree volume tool
Volume calculator from dimensions
Choose a shape, enter its inside dimensions, and calculate volume in liters. The tool shows the formula and useful conversions so you can check the answer.
Shapes
Which shape should you choose?
Cylinder
Drums, pipes, vats, and round tanks.
Read the guide: How to calculate cylinder volume in litersSphere
Spherical vessels and completely round objects.
Read the guide: How to calculate sphere volume in litersCone
Funnels and circular containers that narrow to a point.
Read the guide: Usable capacity vs geometric volumeMethod
How to get a dependable answer
- Measure the available space inside the container.
- Use the same unit for every field.
- Divide a diameter by two before entering it as a radius.
- Allow a safety margin when the container will not be filled to the top.
1 L = 1,000 cm³
Conversions used to check the result
One liter is exactly 1,000 cm³, while one cubic meter is 1,000 liters. For millimeters, inches or feet, each length is converted to meters before the shape formula is applied, preventing mixed-unit calculations.
Calculated result
How to use the answer responsibly
Geometric volume versus usable capacity
The main figure describes an ideal shape. A fish tank loses capacity to glass thickness, substrate and equipment, while a storage tank may have curved corners, pipes or a lower operating fill line. Work from inside dimensions, then make adjustments that match the real container.
A quick independent check
A container measuring 36 × 18 × 16 inches has a geometric capacity of about 170 liters, or roughly 45 US gallons. Repeating the calculation in cubic inches and converting the final value is a useful way to catch a misplaced decimal or an incorrect unit selection.
When geometry is not enough
Do not rely on a simple estimate for structural loading, pressure, chemical dosing, medical use or regulatory compliance. Compare the result with manufacturer documentation, a calibrated vessel, a meter reading or qualified advice. Keep the unrounded value until the final step when small differences matter.