Converting Pounds Per Square Inch or PSI to Millibars

Worked Pressure Unit Conversion Problem

PSI and millibar are two common pressure units.
PSI and millibar are two common pressure units. Ryan Etter, Getty Images
by Anne Marie Helmenstine, Ph.D.
Updated March 06, 2017

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

Problem:

The average air pressure at sea level is 14.6 psi. What is this pressure in mbar?

Solution:

1 psi = 68.947 mbar

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

pressure in mbar = (pressure in psi) x (68.947 mbar/1 psi)
pressure in mbar = (14.6 x 68.947) mbar
pressure in mbar = 1006.6 mbar

Answer:

The average sea level air pressure is 1006.6 mbar.