Temperature Humidity Index (THI) Calculator Online

Last updated on by Editorial Staff

Temperature Humidity Index Calculator


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Quick Guide to Use This Calculator

  • Step 1: Select the temperature unit (Celsius or Fahrenheit) using the dropdown menu.
  • Step 2: Enter the ambient or dry-bulb temperature in the designated input field.
  • Step 3: Enter the relative humidity in percentage in the respective input field.
  • Step 4: Click the “Calculate THI” button to get the Temperature Humidity Index (THI) result in the selected unit.
  • Step 5: The result will indicate the stress level for livestock along with the color-coded thermometer.

Color code and ranges are as follows

  • Normal (Less than 68) – Green Color
  • Stress Threshold (68-72) – Yellow Color
  • Moderate-Severe Stress (80-90) – Red Color
  • Severe Stress (90 and above) – Purple Color


THI in Fahrenheit= Tdb – [0.55 – (0.55 x RH/100)] x (Tdb – 58) 

THI in Celsius = 0.8* T(db) + ( RH/100) * (T(db)-14.4) + 46.4

Where T (db) is ambient or dry bulb temperature in Fahrenheit

RH is relative humidity

The Temperature Humidity Index (THI) is a measure that combines ambient temperature and relative humidity to assess the level of stress and discomfort experienced by individuals, especially animals in a given environment.

Who Can Use This Calculator?

Livestock farmers and caretakers can use this calculator to gauge the comfort levels of animals, ensuring optimal conditions for their well-being.

Industries That Can Use This Calculator

Livestock farming industries can use this calculator. This is useful for dairy farms. Others can also use this calculator to trace their livestock’s behavior. 

Benefits of Using This Calculator

  • Helps farmers identify potential stress in livestock due to temperature and humidity.
  • Allows for timely adjustments in animal management practices to ensure their comfort.
  • Aids in preventing heat-related health issues in livestock.


How is THI calculated?

THI is calculated based on the ambient temperature and relative humidity using specific formulas for Celsius and Fahrenheit.

How does high THI affect livestock?

High THI can lead to heat stress in livestock, impacting feed intake, milk production (in dairy cows), and overall animal well-being.

What measures can be taken to reduce THI for livestock?

Providing shade, proper ventilation, and access to cool water are effective measures to reduce THI for livestock.


The Temperature Humidity Index (THI) Calculator is a valuable tool for livestock farmers to assess and manage environmental conditions for their animals.

By considering temperature and humidity, this tool helps ensure the well-being of livestock and contributes to the overall success of livestock farming operations.