Humidity calculations and conversions made easy
The free Vaisala Humidity Calculator allows you to calculate several humidity parameters from one known value. Make unit conversions on the fly, and see the effects of changing ambient conditions, like temperature and pressure.
Calculate or convert: relative humidity, dew point / frostpoint, absolute humidity, water content, mixing ratio, vapor pressure, parts per million, wet bulb temperature.
Eight languages available: English, Chinese, Dutch, German, Finnish, French, Japanese and Portuguese included.
Choose A or B:
A: Use online humidity calculator
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(version 10 or higher)
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B: Download stand-alone humidity calculator
1. Download the Vaisala Humidity Calculator - click on the link and you will get the download file to your email within seconds after filling out the short form.
(version 2.2, updated 2009-11-23, 2.49 MB)
2. Double-click the "Vaisala Humidity Calculator.msi" to start the installation.
3. Follow the installer steps. Shortcuts will be created to the Start menu and Desktop.
4. Double-click the "Vaisala Humidity Calculator" on your Desktop to start the program.
Operating system: Microsoft Windows 98 / 2000 / XP / Vista / 7
Version 2.2 2009-11-23
- Fixed a calculation bug related to user changing both ambient conditions (T, P) at the same time. Now re-calculation happens immediately after condition has been changed.
- Fixed a bug in language negotiation that resulted in "Locale not found" errors in some localization combinations.
- New Vaisala visuals.
Version 2.1 2008-04-23
- Fixed a calculation bug related to user changing ambient conditions (T, P).
Now all values are calculated based on new ambient conditions.
Version 2.0 2008-04-08
- Wetbulb calculation added. User can insert custom psychrometer coefficients.
- All values are calculated after changes in ambient conditions (T, P, gas type).
- Maximum ambient temperature increased to +373 °C (+703 °F).
- Portuguese localization added.
Version 1.3 2007-06-28
- Fixed a bug in pressure unit conversion when converting to or from mmHg/Torr.
Version 1.2 2007-04-05
- Improved accuracy of vapor pressure calculation in high temperatures.
Version 1.1.1 2007-02-01
- Fixed a calculation bug related to using custom gases.
Version 1.1 2007-01-15
- Comma can be used as decimal separator in addition to full stop.
- Improved calculation formula for natural gas in high pressures (above 40 bar).
- Print button introduced. Use to print the whole calculator screen.
- Copy values button introduced. Use to copy/paste calculated values to other programs, e.g. Microsoft Excel.
- Switching from Basic to Advanced mode does not reset the calculation.
- Input error messages are displayed in selected units. E.g. Temperature in Celsius or Fahrenheit.