Aquarium Volume Calculator

How to calculate aquarium capacity

One litre equals 1,000 cubic centimetres. Multiplying the internal dimensions and dividing by 1,000 gives the rectangular water volume.

Formula

length × width × water depth ÷ 1000; decor displacement excluded

Worked example

Internal length (cm)

100

Internal width (cm)

40

Water depth (cm)

45

Applying the formula to these values gives 180 litres.

What should I check?

Use internal dimensions and actual water depth, not the outside tank dimensions. Substrate, equipment and decoration reduce the water volume.

Use the reset button to restore this example. Your inputs are processed in this browser and are not included in a shared calculator link. See our methodology and limitations.