Pounds per Square Inch Calculator

PSI (Pounds per Square Inch) Calculator

Convert pressure from PSI to bar, Pascal, atmospheres, and other standard pressure units.

Last updated: March 2026 | By ForgeCalc Engineering

Bar
2.2063
kPa
220.63
Atm
2.1775
kg/cm²
2.2498
Pascal (Pa)
220632

What is PSI?

Pounds per square inch (PSI) 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.

PSI is widely used in the United States and the UK for tire pressure, scuba tank pressure, and industrial piping systems. In the SI system, the standard unit is the Pascal (Pa), but Bar and Atmospheres are also common in engineering.

Conversion Factors

Standard Equivalents for 1 PSI

Bar0.0689476
Pascal (Pa)6894.76
Kilopascal (kPa)6.89476
Atmosphere (atm)0.068046
kg/cm²0.070307
Torr (mmHg)51.7149

Frequently Asked Questions

What is the difference between PSIG and PSIA?

PSIG (Gauge) measures pressure relative to atmospheric pressure, while PSIA (Absolute) measures pressure relative to a vacuum. PSIA = PSIG + 14.7.

What is standard tire pressure in PSI?

Most passenger cars have a recommended tire pressure between 30 and 35 PSI.

How many PSI is one atmosphere?

One standard atmosphere (1 atm) is equal to exactly 14.696 PSI.

Is PSI used for water pressure?

Yes, residential water pressure is typically between 40 and 60 PSI.

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