Find out exactly how many liters or gallons your fish tank holds.
The Aquarium Volume Calculator works out exactly how much water your fish tank holds based on its inner dimensions — essential for dosing water conditioners, medication, and for stocking your tank safely.
Use the tank's internal measurements, not the outer glass dimensions, for the most accurate figure. Actual water volume is typically 80-90% of this due to substrate, decorations, and not filling to the brim.
A tank measuring 60 × 30 × 35 cm has a volume of 60×30×35 = 63,000 cm³ = 63 liters, which is about 16.6 US gallons.
For a rectangular tank: length × width × height, then converted to gallons or liters depending on your chosen unit.
Use inside (glass-to-glass) measurements for the most accurate water volume, since glass thickness reduces usable space.
Substrate, decorations, and the water line (tanks are rarely filled to the very top) all reduce the real amount of water compared to the tank's theoretical full volume.