Pounds per square inch

Pounds per square inch (PSI) is a unit of pressure or stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one square inch. In terms of SI units, 1 PSI is approximately equal to 6895 Pa.

Definition and conversions

The pound per square inch or, more accurately, pound-force per square inch (symbol: psi or lbf/in² or lbf/in²) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one square inch. In terms of SI units, 1 psi is approximately equal to 6895 pascals (Pa).

Applications

PSI is commonly used in various systems of units, including English Engineering units and the British Gravitational System. It is widely used in the United States for measuring pressure in many contexts, such as tire pressure, scuba tank pressure, natural gas pipeline pressure, among others.

See also

• Pascal (unit)
• Pressure measurement
• Imperial units
• United States customary units