Weather Calculators and Unit Conversions

Calculators ➡︎ These meteorological calculators will help you convert units and compute various parameters from observations.

NOTE: We are gradually converting the calculators to a mobile-friendly format. You may see a mixed appearance for some calculators on a mobile device. The conversion should be completed soon.



Temperature Conversion

heatTemperature Conversion
Enter a temperature (ºF or ºC), then click the corresponding "convert" button to see the result.
Fahrenheit (oF)
Celsius (oC)
heatTemperature Conversion
Enter a temperature in Fahrenheit then click "convert" to see the result.
Fahrenheit (oF)
Celsius (oC)
OR in Celsius
Celsius (oC)
Fahrenheit (oF)


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Calculate the windchill Index

windchillWindchill Calculation
Enter in the air temperature (Tair) in degrees Fahrenheit and wind speed in mph, then click on the Calculate WC to compute the windchill
Tair oF wind (mph)
OR use dew point temperature
Tair oC wind (mph)
heatWindchill Calculation (Fahrenheit and Celsius)
Enter in the air temperature (Tair) in degrees Fahrenheit and wind speed in mph, then click on the Calculate WC to compute the windchill
Temperature ºF
Wind (mph) mph
Windchill = ºF
OR in Celsius
Temperature ºC
Wind (mph) mph
Windchill = ºC


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Relative Humidity Calculator

heatRelative Humidity Calculator (from Dew Point)
Enter in the air temperature (Tair) and dew point temperature (Tdp) in degrees Fahrenheit (oF) or Celcius (oC, second row), then click "Calc RH" to compute the relative humidity (RH).
Tair oF Tdp oF
Tair oC Tdp oC
heatRelative Humidity Calculator
Enter in the air temperature (Tair) and dew point temperature (Tdp) in degrees Fahrenheit (oF).
Fahrenheit (oF)
Tdp oF
Relative Humidity
OR in Celsius
Celsius (oC)
Tdp oC
Relative Humidity


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Heat Index Calculator

heatHeat Index Calculation
Enter in the air temperature (Tair) in degrees Fahrenheit and relative humidity (RH) in percent (without the % sign), then click on the Calculate HI to compute the heat index (HI) | Use the heat index tables
Tair RH HI=
OR use dew point temperature
Tair Tdp HI=
heatHeat Index Calculation
Enter in the air temperature (Tair) in degrees Fahrenheit and relative humidity (RH) in percent (without the % sign), then click on the Calculate HI to compute the heat index (HI) | Use the heat index tables
Temperature ºF
Relative Humidity %
Heat Index =
OR use dew point temperature
Temperature ºF
Dew Point Temp ºF
Heat Index =


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Convert Wind Speed Units

heatWind Speed Conversion
Input value here and then select units below Answers:
mph mph
knots knots
m/s m/s
ft/s ft/s
km/h km/h


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Wet-Bulb Calculator

heatWet-Bulb Temperature from Dewpoint
Temp: Dewpoint: Pressure*:

Fahrenheit
Celsius
Kelvin

Fahrenheit
Celsius
Kelvin
in. of mercury
mm of mercury
mb (hPA)
*not altimeter setting
Conversion/Answers
Wet-bulb temperature:
ºF  ºC  K
Rel Humidity: %