Aquarium Volume Calculators

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Knowing your tank's volume is vital when using treatments or working out stocking values. Use these aquarium volume calculators to help

It is a good idea to write down your volume and keep it somewhere safe (e.g. on the inside of your aquarium cabinet door)

You can take off roughly 10% of your volume to account for decor (rocks, gravel etc.) and space above the water line.

Choose your tank shape from the calculators below, enter your tanks measurements in centimetres (cm) and click 'calculate' to work out your tanks volume.


Convert inches to Centimetres

If you prefer to measure in inches use the converter below to change your measurements to centimetres

IN x 2.54 = CM | FT x 30.48 = CM

Fishtank Volume
Rectangular / Square tanks

diagram of rectangle tank
Width (cm)
Length (cm)
Height (cm)

Your fish tank volume is:
Litres
Imperial Gallons
US Gallons

Fishtank Volume
Cylindrical fish tanks

diagram of cylindrical tank

Diameter (cm)
Height (cm)

Your fish tank volume is:
Litres
Imperial Gallons
US Gallons

Fishtank Volume
Corner tanks

diagram of corner tank
Distance A (cm)
Distance B (cm)
Height (cm)

Your fish tank volume is:
Litres
Imperial Gallons
US Gallons

Fishtank Volume
Hexagon tanks

diagram of hexagon tank
Distance A (cm)
Distance B (cm)
Height (cm)

Your fish tank volume is:
Litres
Imperial Gallons
US Gallons

Fishtank Volume
Octagon tanks

diagram of octagon tank
Distance A (cm)
Distance B (cm)
Height (cm)

Your fish tank volume is:
Litres
Imperial Gallons
US Gallons

Fishtank Volume
Spherical tanks

diagram of spherical tank
Enter the circumference of your tank below to work out the radius. Radius is also half the diameter, or height, of your sphere.

Enter your radius below:
Radius (R)

Your fish tank volume is:
Litres
Imperial Gallons
US Gallons

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