Calculate dew point, heat index, and comfort level from temperature and relative humidity
Conditions
Comfort level: Slightly humid
Dew Point
16.7°C
62.1°F
Spread
8.3°C
temperature − dew point
Abs. Humidity
13.8
g/m³
Heat Index
—
applies above 80°F / 40% RH
Comfort Scale (dew point)
DryBelow 10°C
Comfortable10–15°C
Slightly humid16–17°C
Humid18–20°C
Very humid21–23°C
OppressiveAbove 24°C
This dew point calculator uses the Magnus formula to compute the dew point temperature from dry-bulb temperature and relative humidity. It also shows the heat index (apparent temperature) when conditions are hot and humid, absolute humidity in g/m³, and a color-coded comfort scale.
How to Use
- 1Enter the air temperature in °C or °F.
- 2Enter the relative humidity as a percentage (0–100).
- 3The dew point and comfort level update instantly.
- 4Use the unit toggle button to switch between Celsius and Fahrenheit.
- 5Heat index appears when temperature is above 27°C (80°F) and humidity is above 40%.
Frequently Asked Questions
What is the dew point?
The dew point is the temperature at which air must be cooled (at constant pressure) for water vapor to start condensing into dew. Higher dew points feel more humid.
How does dew point relate to comfort?
Dew points below 10°C feel dry, 10–15°C comfortable, 16–17°C slightly humid, 18–20°C humid, 21–23°C very humid, and above 24°C feel oppressive or tropical.
What formula is used?
The Magnus formula is used for dew point. The NOAA Rothfusz regression equation is used for heat index when applicable (T≥80°F, RH≥40%).