Relative Humidity Converter Enter a temperature and a pressure or a dewpoint and a pressure or both a temperature and a dewpoint and a pressure: If you want the saturated mixing ratio enter the air temperature: Saturated mixing ratio: Fahrenheit Celsius Kelvin grams per kilogram If you want the actual mixing ratio enter the dewpoint: Actual mixing ratio: Fahrenheit Celsius Kelvin grams per kilogram Enter your actual station pressure (not the altimeter setting): relative humidity - requires both temp and dewpoint in of Mercury mm of Mercury millibars (hPA) % If you enter both a Temperature and Dewpoint you'll get a bonus answer.