Aquarium Volume Calculator
Calculate rectangular aquarium volume in liters, US gallons and UK gallons.
How to Use the Aquarium Volume Calculator
Enter the tank dimensions to estimate aquarium volume.
Practical Example
A rectangular tank measuring 100 cm × 40 cm × 50 cm has a gross volume of 200 liters.
Factors That Affect the Result
Substrate, decorations, water level, glass thickness and irregular tank shapes reduce usable water volume.
Frequently Asked Questions
Is gross volume the same as usable water volume?
No.
Should decorations be subtracted?
Yes for a more realistic estimate.
Can I use inches?
Yes if the calculator supports that unit system.
From Tank Dimensions to Usable Water Volume
Rectangular aquarium volume is based on internal length, width and water height. Manufacturer dimensions may be external, and substrate, rocks, equipment and an unfilled top section reduce actual water volume. Use internal measurements when dosing or planning capacity.