Temperature, Dewpoint, and Relative Humidity Calculator

Try out our online relative humidity, dew point, and temperature calculator and learn how to calculate dew point with temperature and humidity or how to calculate relative humidity with temperature and dew point.

Temperature, Dewpoint, and Relative Humidity Calculator

Humidity can affect our overall well-being and comfort so it is important to be able to calculate it to easily control our environment. Temperature (T), relative humidity (RH), and dewpoint (DP) are utilized and compared to safeguard the quality of our living spaces. For example, in humid and hot conditions it may be difficult to keep cool which adds to our discomfort.

How to use this humidity calculator?

First, you must choose whether you wish to use Fahrenheit or Celsius to use the humidity calculator then fill in 2 of the fields below and click the calculate button. The result will appear in the blank field.

• Fahrenheit (ºF) / Celsius (ºC)
• Temperature — T (°)
• Dew point — Td (°)
• Relative Humidity — RH (%)

Relative Humidity and Dew Point Calculator

What is relative humidity?

Humidity is the amount of water vapor in the air, this means that dew, frost, or fog are present. There are 2 types of humidity: absolute humidity and relative humidity. Relative humidity is mostly used in everyday situations and it is essential to know how to calculate relative humidity from the dew point. 

Absolute humidity is the measure of water vapors known as moisture in the air regardless of the temperature. 

Relative humidity, on the other hand, is used to indicate precipitation, dew, frost, or fog. This affects the apparent temperature that is felt by people. For example, there will be more relative humidity in cool air than in warmer air. When the conditions reach 100% relative humidity, this means that dew can appear. 

To avoid humidity from affecting our environment negatively, it is key to calculate the dew point relative humidity temperature. An RH calculator wet bulb is essential to prevent our bodies from overheating or freezing. The wet bulb calculator is easy to use, it can help you figure out the wet bulb temperature from just 2 numbers: temperature (T) and relative humidity (RH). This is why knowing how to calculate relative humidity is pivotal in improving the quality of our environment.

What is Dew Point?

The dew point is when the temperature at a given volume of air in relation to atmospheric pressure is saturated with water vapors that then cause condensation which appears as dew. Dew can often be seen on grass or flowers during early morning hours. The dew point will change depending on the amount of water vapor in the air at any given time. For example, humid air will have a higher dew point than dry air. When relative humidity reaches 100% in relation to air temperature, this is when dew, frost, and fog appear, this is called the dew point.

How does this affect our comfort level? Simply put, when the temperature is high, humans sweat to cool down. How quickly our sweat will evaporate is directly linked to the moisture in the air. If the air is humid then our perspiration will not evaporate as quickly making our condition less comfortable. The more we sweat the less comfortable we are.

Being able to calculate dew point humidity can aid us in adjusting the temperature of our environment and subsequently make it more comfortable and pleasant. High humidity can have many adverse effects on the human body, notably, it can decrease our energy levels. It can also contribute to a plethora of other health issues. How to calculate humidity and understanding dew point levels are essential for our well-being.

How to calculate the dew point and relative humidity?

Relative humidity, dew point, and temperature are related to one another. You can easily calculate the dew point from relative humidity and temperature. However, determining the relative humidity requires additional data.

Dew point Calculation Formula

It's easy to calculate the dew point if you know the relative humidity and temperature.

• Equation: Td = T - ( (100 - RH)/5)

In this equation, Td is the dew point, and RH means relative humidity.

Important note: the results will be in Celsius. To calculate the dew point in Fahrenheit, use the following formula:

ºF = ( °C × 9/5 ) + 32

However, you can always use our dew point temperature calculator, which shows results in Fahrenheit and Celsius.

Relative Humidity Calculation Formula

There's no easy way to calculate relative humidity. Here are some formulas you can use:

• Equation 1: RH = E/Es × 100

In this equation, RH means relative humidity, E is the amount of water vapor, and Es refers to the amount of water content that would be in the air with an equal temperature and pressure level.

• Equation 2: RH = 100 × E × ( (243.04 × 17.625 (Td−T) ) / ( (17.625 + T) × (17.625 +Td) )

Td refers to the dew point, and T refers to air temperature in this equation. 

• Equation 3: RH = 100% × AH × AHmax

Here, AH means absolute humidity, and AHmax is the maximum level of absolute humidity.

Absolute Humidity Calculation Formula

You can also calculate absolute humidity from relative humidity and temperature.

• Equation: AH = ( 6.112 × E^ × [(17.67 × T) / (T + 243.5)] × RH × 2.1674 ) / ((273.15 + T)

As before, T means temperature, and RH stands for relative humidity. The E^ equals 2.71828.

Conclusion

If you need help with dew point temperature calculation or want to know how to calculate relative humidity, please contact us at (847) 773-1023 and our specialists will answer all your questions regarding relative humidity and dew point.