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How Much Aquarium Substrate Do I Need?
Work out exactly how much gravel, sand or aqua soil your tank needs, the right depth, and how many bags to buy.
Read more →Fish Tank Measurement Calculator
Volume
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Enter your tank dimensions to see the volume.
Did we solve your problem?
Turn simple tank measurements into a precise volume. Enter length, width and height and read the capacity in litres and gallons.
Measuring your tank correctly
Measure the inside of the tank, not the outer glass, and keep all measurements in the same unit. Multiply length by width by height, and the calculator converts the result to litres, gallons and cubic centimetres.
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
Formula
V = length × width × height Related calculators
Frequently asked questions
How do I measure a fish tank for volume?
Measure the internal length, width and height in the same unit, then enter them into the calculator.
What if my tank is an unusual shape?
Pick the matching shape, such as cylinder, hexagon or corner, and the right formula is applied automatically.
Should measurements be internal or external?
Internal, because the glass thickness does not contribute to the water volume.
What unit should I measure in?
Centimetres are easiest because they convert cleanly to litres, but inches and feet also work.
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.
Related guides
Learn the core ideas behind fish tank volume before or after using the calculator.
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