what is atmospheric pressure at sea level

The atmospheric pressure at sea level is approximately 1013.25 millibars or 14.7 pounds per square inch. This is the average pressure at mean sea level (MSL) in the International Standard Atmosphere (ISA) . Weather maps showing the pressure at the surface are drawn using millibars. The pressure decreases by about 1.2 kPa (12 hPa) for every 100 meters above sea level.