Pressure Conversions – Atm to PSI

Old-barometers psi to atm
Mercury barometers are used to measure air pressure. Credit: Edal Anton Lefterov/Creative Commons

Pressure is a measurement of force per unit area. Atmospheres (atm) and pounds (force) per square inch (PSI) appear on many pressure gauges on scientific instruments. This example problem shows how to convert atm to PSI units.

Example Problem:
The pressure at sea level is generally considered to be 1 atm. Pressure increases the deeper you dive in the ocean by roughly 1 atm every 10 meters. At a depth of 2 km (2000 m), the pressure will be 200 atm. What is this pressure in PSI?

The relationship between atm and psi is:

1 atm = 14.696 PSI

Multiply 200 atm by the conversion factor to calculate PSI.

atm to PSI conversion math step 1
? PSI = 2939.2 PSI

The pressure at a depth of 2 km is 2939.2 PSI.

For further explanation of using conversion factors in this way, check out How to Convert Units and the Ladder Method.