How to Calculate Dew Point
What is Dew Point?
A dew point calculator determines the temperature at which air becomes saturated (100% relative humidity) and moisture condenses, based on air temperature and relative humidity. Dew points above 21°C (70°F) feel uncomfortably humid; below 10°C (50°F) the air feels dry. The Magnus formula approximates dew point to within 0.4°C.
Step-by-Step Guide
- 1Measure temperature and humidity
- 2Apply Magnus formula
- 3Calculate dew point
Worked Examples
Input
25C, 60% humidity
Result
~14C dew point
When condensation starts
Common Mistakes to Avoid
- ✕Not double-checking results
- ✕Ignoring edge cases
Frequently Asked Questions
What does this calculator do?
Input values
How do I use this calculator?
System calculates
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