What is air pressure at sea level in all the different units of pressure?

Standard air pressure at sea level is 1 atmosphere, or 1 atm.  This is the standard value, but it will not always equal this value due to changes in weather.

In different all the different units of pressure this is equivalent to:

1 atm = 14.6959488 pounds per square inch

1 atm = 29.9246899 inches of mercury

1 atm = 760 mm mercury

1 atm = 760 torr

1 atm = 101 325 pascals

1 atm = 1.01325 bar

Normal Atmospheric Pressure at Sea Level

'Standard' atmospheric pressure is defined at sea level as 101,325 pascals (newtons per square metre), 760 millimetres of mercury or about 1 bar (1000 millibar). These numbers are equivalent values using different measurement systems. Naturally air pressure varies with the prevailing weather conditions, but usually by no more than about 10% either above or below.

Answer

14.7 pounds per square inch. This varies quite a bit though, as the local weather changes. Also, 14.7 PSI is the atmospheric pressure at sea level this drops as we gain altitude, as a for instance, Denver approximately 1 mile above sea level has an atmospheric pressure of approximately 12.2 PSI since 986.9 millibar equals 14.7 PSI 12.2 PSI equals 819.1 millibar and as Low or high pressure cells move into any area, the atmospheric pressure will vary in kind.

First answer by JEK. Last edit by JEK. Contributor trust: 1776 [recommend contributor]. Question popularity: 70 [recommend question]