All barometric pressures (like those seen on the weather reports) are converted to mean sea level (MSL) pressures. This handy calculator does the same as long as you know your actual physical elevation above sea level. This calculator is in metric units.

temperaturethe current station temperature
atmospheric pressurethe current station barometric pressure
elevationthe actual elevation above sea level of the station
mean sea level pressurecalculated barometric pressure with sea level as the reference point
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