A square inch (plural: square inches) is a unit of area, equal to the area of a square with sides of one inch.
The following symbols are used to denote square inches: The square inch is a common unit of measurement in the United States and the United Kingdom.
A common unit of pressure, pound per square inch (psi) is derived from this unit of area.
1 square inch (assuming an international inch) is equal to: (the overbars indicate repeating decimals)