About the HR/BW Calorie Burn Calculator
This tool estimates exercise calories burned from your average heart rate, body weight, age, sex, and workout time. It is most useful for steady aerobic sessions, such as running, cycling, rowing, or elliptical workouts, where you know your average heart rate for the active portion.
How to use this calculator
- Select the sex used in the equation.
- Enter your age, body weight, and choose lb or kg.
- Enter your average heart rate during the workout in bpm.
- Enter the workout duration in minutes and your resting heart rate.
- Click Calculate to see estimated calories, calories per minute, max heart rate, and intensity percentages.
- Use Reset to restore the default example values.
How it works
The calculator first converts body weight to kilograms if pounds are selected. It then applies a published heart-rate calorie equation based on sex, using age, weight in kilograms, average heart rate, and duration.
For males, calories per minute are estimated from age, weight, and heart rate with a male-specific equation. For females, a different equation is used that weights the same variables differently. The result is multiplied by workout duration to estimate total calories burned.
The calculator also estimates maximum heart rate as 220 minus age. It uses that value to calculate percent of max heart rate and, with your resting heart rate, percent heart rate reserve. Intensity labels are based on percent of max heart rate: light, moderate, aerobic, hard, or peak.
Results are educational fitness estimates only and are not medical advice. Actual calorie burn can vary with fitness level, medications, heat, hydration, exercise type, and measurement accuracy.
Example calculation
Using the default values: male, age 35, weight 175 lb, average heart rate 145 bpm, duration 45 minutes, and resting heart rate 65 bpm. The weight converts to about 79.4 kg, giving an estimated burn rate of about 12.9 kcal/min. Over 45 minutes, the estimated total is about 581 kcal, with an estimated max heart rate of 185 bpm and about 78% of max heart rate.
Frequently asked questions
How accurate is a heart-rate calorie estimate?
It is a useful estimate for steady aerobic exercise, but it can differ from lab testing or wearable devices because heart rate is affected by fitness, temperature, stress, caffeine, medications, and fatigue.
Should I use average or peak heart rate?
Use your average heart rate for the active workout period. Peak heart rate will usually overestimate calories because it does not represent the whole session.
Why does the calculator ask for resting heart rate?
Resting heart rate is used to calculate percent heart rate reserve, which gives additional context about workout intensity. It is not used directly in the calorie equation.
What if my workout includes intervals?
The estimate can still be used if your average heart rate represents the full active session, but intervals may be less precise because heart rate can lag behind sudden changes in effort.
Why are male and female results different?
The calculator uses separate published equations for males and females, with different coefficients for age, body weight, and heart rate.