to sea level pressure.

with BMP85/180/280 and BME280 sensors.

1. The BOSCH formula assumes a standard temperature of 15 degrees Celsius.

This formula is good when placing a barometer in the interior:

2. Babinet's formula. The formula is very accurate for altitudes less than 500m:

3. Modified ICAO formula. Probably the most versatile formula:

p0 | [Pa] | pressure at sea level |

p | [Pa] | absolute pressure obtained by measurement |

t | [C] | air temperature in degrees Celsius |

h | [m] | altitude of the measuring station |