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Fish Tank Volume Calculator

Fish Tank Volume Calculator in Feet



Volume

Enter your tank dimensions to see the volume.

Did we solve your problem?

Calculate aquarium volume from measurements in feet. Enter the dimensions in feet and the result is shown in litres and gallons.

Working in feet

If you measured your tank in feet, the calculator converts to volume for you. Multiply length, width and height in feet to get cubic feet, then convert to litres and gallons.

Volume at a glance

Drag to fill a 60 by 30 by 30 cm (54 L) tank and watch the volume change.

50% full = 27 L

How to calculate fish tank volume

Measure the length, width and height of your tank, then multiply them together. Change the values below and the diagram and the calculation update instantly.

  1. 1

    Measure length, width and height

    60 x 30 x 30 cm

  2. 2

    Multiply them for cubic centimetres

    60 x 30 x 30 = 54,000 cm³

  3. 3

    Convert to litres and gallons

    54,000 ÷ 1000 = 54 litres (14.27 US gal)

Formulas behind the fish tank volume calculator

Prefer to calculate the aquarium size by hand? Here is the volume formula for each tank shape. Click a card to try it in the calculator.

For unusual tanks, see a triangular prism volume tool, and note that spherical aquariums (fish bowls) are not recommended for keeping fish.

Aquarium shapes

Our fish tank volume calculator supports seven popular aquarium shapes. Click any shape to load it into the calculator above.

Frequently asked questions

How do I calculate fish tank volume in feet?
Enter the dimensions in feet and the calculator converts them to litres, gallons and cubic centimetres.
How many gallons in a cubic foot?
One cubic foot of water is about 7.48 US gallons or 28.3 litres.
How big is a 4x2x2 foot tank?
That is 16 cubic feet, roughly 453 litres or 120 US gallons.
Can I mix feet and inches?
Convert everything to one unit first. Pick feet or inches in the calculator and use that throughout.
What units can I use in this calculator?
You can switch between centimetres, millimetres, inches, feet and metres at any time. Enter all dimensions in the same unit and the result updates instantly.
Does the result include substrate and decoration?
The figure is the full internal capacity. Subtract roughly 10 to 15 percent for substrate, rocks and the gap you leave at the top to estimate the real water volume.
How accurate is this fish tank calculator?
It uses the exact geometric formula for each shape, so the result is accurate for the dimensions you enter. Measure the inside of the tank for the best accuracy.
Is this calculator free to use?
Yes. It is completely free, needs no sign-up, and works on phones, tablets and desktops.

Calculator tools

Explore our specialised fish tank volume calculators, each tailored for a specific unit, shape or region.

Related guides

Learn the core ideas behind fish tank volume before or after using the calculator.