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Heart Rate Calorie Calculator
Calories from your average heart rate, using the Keytel equation.
Results
- Calories in 45 min
- 383 kcal
Keytel et al. (2005)
kcal/min from HR, weight, age, sex (and VO₂max if given)
Heart-rate estimates suit steady cardio best; they overstate short, intense intervals.
A heart rate calorie calculator estimates energy use from your average beats per minute during exercise. Higher heart rate means higher oxygen use and more calories.
This calculator uses the Keytel equation; adding VO₂max switches to the fitness-adjusted version for a closer estimate.
How to calculate calories from heart rate
To calculate calories from heart rate, the Keytel equation combines average heart rate with weight, age, and sex. It works best for continuous aerobic exercise.
Worked example: a 70 kg man, age 30, at 140 bpm for 45 minutes burns about 500 calories.
Frequently asked questions
Yes for steady cardio, within about 10–15%. It is less accurate for lifting and interval work, where heart rate lags effort.
No. The calculator works without it, but adding VO₂max sharpens the estimate for trained athletes.
Most wearables blend heart rate with motion and your body profile, which is why two devices disagree by 10–20%.
Results are estimates based on population averages and are not medical advice. Consult a doctor or registered dietitian nutritionist (RDN) before making large changes to your diet, especially for deficits over 2 lb (0.9 kg) per week, during pregnancy or nursing, or for anyone under 18.