Enter the air temperature and the relative humidity into the calculator to estimate the feels like temperature.

Temperature With Humidity Calculator

Use the main tab to estimate feels-like temperature from air temperature and humidity. Use the second tab to solve for dew point, air temperature, or relative humidity.

Feels Like / Heat Index
Dew Point / RH / Temperature
Enter temperature and humidity to calculate the heat index, also called the feels-like temperature.
Enter any two values to calculate the missing one using a Magnus-based approximation.

Related Calculators

Dew Point (Approximation) Formula

The following rule-of-thumb formula is commonly used to estimate the dew point from the air temperature and relative humidity. (It is not a “feels like” / heat index calculation.)

T_d = T - \frac{(100 - H)}{5}

Variables:

  • Td is the dew point temperature (approx.) in degrees Celsius (°C)
  • T is the air (dry-bulb) temperature in degrees Celsius (°C)
  • H is the relative humidity in percent (%)

To estimate the dew point, subtract the quotient of (100 minus the relative humidity) divided by 5 from the air temperature (with temperatures expressed in °C).

What is the Effect of Humidity on Temperature?

Relative humidity describes how close the air is to being saturated with water vapor at a given temperature. Humidity does not directly change the air temperature measured by a thermometer, but it does affect other temperature-related quantities—especially the dew point, which is the temperature at which the air becomes saturated (100% relative humidity) and condensation can begin. Higher humidity generally means a higher dew point, which is associated with “muggier” conditions and increased condensation risk. If you’re looking for a “feels like” temperature for human comfort, use a heat index / felt air temperature calculation instead.

How to Calculate Dew Point (Approx.)?

The following steps outline how to estimate the dew point from air temperature and relative humidity using the approximation above.

  1. Measure the air temperature (T).
  2. Measure the relative humidity (H) in percent (%).
  3. Convert the temperature to degrees Celsius (°C) if it is not already in °C.
  4. Use the formula Td = T − (100 − H) / 5 to estimate the dew point.
  5. Check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Air Temperature (T) = 30°C

Relative Humidity (H) = 60%

Dew Point (Td) ≈ 30 − (100 − 60)/5 = 30 − 8 = 22°C