Units of volume | Customary units of measurement in the United States | Imperial units
Cubic inch
The cubic inch (symbol in3) is a unit of volume in the Imperial units and United States customary units systems. It is the volume of a cube with each of its three dimensions (length, width, and height) being one inch long which is equivalent to 1/231 of a US gallon. The cubic inch and the cubic foot are used as units of volume in the United States, although the common SI units of volume, the liter, milliliter, and cubic meter, are also used, especially in manufacturing and high technology. One cubic inch is approximately 16.387 mL. One cubic foot is equal to exactly 1,728 cubic inches (28.32 L) because 123 = 1,728. One US gallon is equal to exactly 231 cubic inches (3.79 L). (Wikipedia).
