What is a PSI?

Definition
psi

Pounds per square inch (psi) is an imperial pressure unit widely used in the US for tire pressure, hydraulics, and gas pressure.

Unit system
Imperial
All pressure units
UnitSymbolSystem
pascals Pa SI / Metric
kilopascals kPa SI / Metric
megapascals MPa SI / Metric
bar bar SI / Metric
millibars mbar SI / Metric
PSI psi Imperial
atmospheres atm Reference
torr Torr Scientific
mmHg mmHg Medical
inches of mercury inHg Aviation
inches of water inH₂O Engineering