Calculate capacity and fill volumes of common tank shapes for water, oil or other liquids. 7 tank types can be estimated for gallon or liter capacity and fill. How to calculate tank volumes.
Although most tanks represent their volume based on external dimensions, actual volume must be measured from the internal dimensions if you are looking for accuracy …. as opposed to just a directional number. For example, a 48x15x21 tank measured from external dimensions will be nominally 65 gallons; internally, it'll be more like 55 gallons.