Glaister Equation Calculator

The Glaister Equation Calculator is a tool designed to estimate heart rate (HR) based on body temperature (°C). This calculator utilizes the Glaister Equation, which provides a simple yet effective means of estimating heart rate under normal physiological conditions.

Formula: The Glaister Equation is given by: HR = 98.4 + 0.41 * (T – 36.9)


  • HR is the estimated heart rate.
  • T is the body temperature in Celsius (°C).

How to use:

  1. Input the body temperature in Celsius (°C) into the designated field.
  2. Click the “Calculate” button to obtain the estimated heart rate.

Example: Suppose a person has a body temperature of 37.5°C. Using the Glaister Equation Calculator, the estimated heart rate would be calculated as follows: HR = 98.4 + 0.41 * (37.5 – 36.9) HR ≈ 98.4 + 0.41 * 0.6 HR ≈ 98.4 + 0.246 HR ≈ 98.646 bpm


  1. What is the Glaister Equation?
    • The Glaister Equation is a mathematical formula used to estimate heart rate based on body temperature.
  2. What units are used for body temperature in this calculator?
    • Body temperature should be entered in Celsius (°C).
  3. Is the Glaister Equation suitable for all individuals?
    • The Glaister Equation provides a general estimation and may not be accurate for all individuals, especially those with certain medical conditions.
  4. Can I use this calculator for medical diagnosis?
    • This calculator is intended for educational and informational purposes only and should not be used for medical diagnosis or treatment.
  5. How accurate is the Glaister Equation?
    • The accuracy of the Glaister Equation may vary depending on individual factors and conditions.
  6. What is the significance of 98.4 in the formula?
    • The constant 98.4 represents the average resting heart rate under normal conditions.
  7. Is the Glaister Equation suitable for athletes?
    • Athletes may have different resting heart rates, so the Glaister Equation may not be as accurate for them.
  8. Can body temperature affect heart rate?
    • Yes, variations in body temperature can influence heart rate as the body works to maintain homeostasis.
  9. Are there any limitations to using the Glaister Equation?
    • Like any estimation method, the Glaister Equation has limitations and may not account for all factors influencing heart rate.
  10. Can I use this calculator for medical research?
    • While this calculator provides estimations, it is not intended for rigorous medical research purposes.

Conclusion: The Glaister Equation Calculator provides a convenient way to estimate heart rate based on body temperature. While it offers a quick approximation, it’s important to remember that individual variability and other factors may influence the accuracy of the results. This tool can be useful for educational purposes and as a general guideline for understanding the relationship between body temperature and heart rate.