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Fish Tank Volume Calculator

Triangle Fish Tank Volume Calculator



Volume

Enter your tank dimensions to see the volume.

Did we solve your problem?

Calculate the volume of a triangular or corner-triangle aquarium. Enter the two base sides and the height to get the capacity in litres and gallons.

How triangle tank volume works

A triangular tank usually has a right-triangle base with two straight sides meeting at the corner. The volume is half of length times width times height, which the calculator applies for you.

Shape preview

Adjust the size and height to see this tank shape and its volume.

Volume ≈ litres

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 triangle fish tank volume?
Enter the two base lengths and the height. The volume is half of length times width times height.
What shape is a triangle fish tank?
Most are corner tanks with a right-triangle base, fitting neatly into the corner of a room.
How do I get the result in gallons?
Switch the result unit to US or UK gallons after entering your dimensions.
Why is the volume halved?
A triangle is half of a rectangle with the same base and height, so the box volume is halved.
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.