A square inch (plural: square inches) is a unit of area, equal to the area of a square with sides of one inch. The square inch is a common unit of measurement in the United States and the United Kingdom. Pounds per square inch (psi), a unit of pressure, are derived from this unit of area.
Representations
The following symbols are used to denote square inches:
- square in
- sq inches, sq inch, sq in
- inches/-2, inch/-2, in/-2
- inches^2, inch^2, in^2
- inches<sup>2</sup>, inch<sup>2</sup>, in<sup>2</sup> (also denoted by "<sup><sup>2</sup></sup>)
- historic usage <sup>â¡</sup>â³ (number with a square & a double apostrophe, both as an exponent)
Equivalence with other units of area
1 square international inch is equal to (the overbars indicate repeating decimals):
- square feet (1 square foot is equal to 144 square inches)
- square yards (1 square yard is equal to 1,296 square inches)
- square centimetres (1 square centimetre is equal to square inches)
- square metres (1 square metre is equal to square inches)
- circular inches (1 circular inch is equal to square inches)
References