Converting Pounds Per Square Inch or PSI to Atmospheres

This example problem demonstrates how to convert the pressure unit pounds per square inch (psi) to atmospheres (atm).

Problem:

A bicycle tire is inflated to 65 psi. What is this pressure in atmospheres?

Solution:

1 atm = 14.696 psi

Set up the conversion so the desired unit will be cancelled out. In this case, we want atm to be the remaining unit.

pressure in atm = (pressure in psi) x (1 atm/14.696 psi)
pressure in atm = (65/14.696) atm
pressure in atm = 4.423 atm

Answer:

The average sea level air pressure is 4.423 atm.