Known ParameterThe humidity parameter that is known. e.g. Dew Point
Known ValueThe value of the known parameter.
Known UnitsThe unit of measurement of the known parameter. e.g °C
Sample PressureThe pressure at the point where the humidity measurement is made. Defaults to atmospheric pressure.
Pressure UnitsThe unit of measurement of the sample pressure. e.g. Pascals
Pressure CompensationIf conversion to another pressure is required, enter that pressure in this box. The measurement units will be the same used for the Sample Pressure.
Gas TypeChoose from a list of preset molecular weights. Used only for ppmW & mixing ratio calculations. A user-defined molecular weight can be entered by selecting 'User'.
Mol. WeightMolecular weight of gas being measured, used only for ppmW/Mixing Ratio calculations.
Sample TemperatureThe temperature at the point where the humidity measurement is made.
Temperature UnitsThe temperature units to use for all temperature parameters including sample temperature, dew-point, frost-point and wet bulb. e.g. °C
WMO Standard for %RHSaturation vapour pressure is calculated over water even for temperatures below freezing as per WMO standard.
Rounding WeightTotal number of digits to show when rounding. Default 5.
While every effort has been made to ensure the formulae used in this calculator are correct, this free software service is provided 'as-is' and without warranty or guarantee to the extent of the applicable law.