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Fish Tank Volume Calculator

Fish Tank Volume Calculator (Metric)



Volume

Enter your tank dimensions to see the volume.

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A fully metric fish tank volume calculator. Enter your dimensions in centimetres and read the volume in litres and cubic metres.

Metric aquarium volume

In metric units, multiply length by width by height in centimetres for cubic centimetres, then divide by 1000 for litres or by 1,000,000 for cubic metres.

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 metric units?
Measure in centimetres, multiply the three sides, and divide by 1000 for litres or by a million for cubic metres.
How many litres in a cubic metre?
One cubic metre equals 1000 litres.
How big is a 1 metre tank?
A 100x40x50 cm tank holds 200 litres, which is 0.2 cubic metres.
Can the calculator show gallons too?
Yes, switch the result unit to US or UK gallons at any time.
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

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