How to use the Dew Point Calculator
The dew point calculator finds the temperature at which air becomes saturated, from temperature and humidity.
Open the Dew Point Calculator →
What you need to enter
- Air temperature (°C)
- Relative humidity (%)
The formula
It uses the Magnus formula with a = 17.625 and b = 243.04 °C.
Worked example
Using the default values in the calculator:
- Air temperature (°C): 25
- Relative humidity (%): 60
| Dew point | 16.7 °C |
| In Fahrenheit | 62.1 °F |
| Comfort | Slightly humid |
Tips for better results
- A higher dew point feels more humid.
- Condensation forms when surfaces fall below it.
Common mistakes to avoid
- Mixing °C and °F.
- Entering humidity as a decimal.
Please note: Results are estimates for general use. For safety-critical work such as electrical or building projects, check with a qualified professional and local codes. See our Disclaimer.