Original: Pressure and thickness The average atmospheric pressure , at sea level , is about 1 atmosphere ( atm ) = 101.3 kPa ( kilopascals ) = 14.7 psi ( pounds per square inch ) = 760 torr = 29.9 inches of mercury ( symbol Hg ) .
Simplified: The average pressure of the atmosphere at sea level is about 101.4 kilopascals ( about 14.7 pounds per square inch ) .