# Aquarium Volume Calculator



## tedrock (Jul 11, 2007)

*Aquarium Volume Calculator*
For all those folks that come here and post the question "How many gallons is this tank?" and provide the measurements. It does U.S. gallons and liters.

Ignore the comments the site makes on your tank size. They are directed towards fish not frogs. Some of it stands true though.


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## AccidentalChef (Jun 29, 2007)

The math for this stuff is actually pretty simple... length * width * height (in inches) divided by 231 gives you the volume in gallons. For example, a 20x12x10 tank:

20 * 10 * 12 = 2400
2400 / 231 = 10.4. The aquarium companies call this size a 10 gallon.

Sometimes it's easier to think in feet than in inches. In these cases, the math would be length * width * height * 7.5 = volume in gallons. This is an approximation, but it's only off by about 0.2%. For example, a 4' x 2' x 2' tank:

4 * 2 * 2 * 7.5 = 120 gallons, which is how the manufacturer describes this size. 

Both of these calculations ignore glass thickness unless you measure inside dimensions, but they should be close enough for any of our purposes. Manufacturer sizes are often just approximations of how many gallons the tank really holds, and they often do ignore glass thickness.


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## brettlt (Oct 5, 2006)

We usually measure aquariums from the outside dimensions, just as Accidentalchef pointed out. 
The only exception that I know of is Oceanic. A 33 Oceanic cube equals 39.4 gallons from outside dimensions, but a little more than 33 gallons on the interior. Oceanic also uses 1/2" glass all around, while most aquariums have thinner glass.


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## tedrock (Jul 11, 2007)

i see the question posted almost once a day so i figured rather having repeat posts about it just provide a tool for the people that don't know the math.


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## Mustang (May 2, 2007)

Here ya go try this one
http://reefcentral.com/calc/vol.php


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## tedrock (Jul 11, 2007)

does the same math as the one i posted but doesn't have additional comments


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## skates94 (Jul 28, 2007)

As a noobie I'm looking at a cube that only gave measurements.... This calculator is great! I was never good with math.


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