Heart rate rises in step with oxygen use, so it is a good guide to how hard you’re working. These equations, from a study of people exercising on treadmills and bikes, are what many fitness watches use.
How to use the Calories Burned by Heart Rate Calculator
- Sex
- Do you know your VO₂ max?
- Age (years)
- Body weight
- Average heart rate (bpm)
- VO₂ max (ml/kg/min)
- Exercise duration
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Choose your sex, whether you know your VO₂ max, then enter age, weight, average heart rate and duration. Valid for heart rates between about 90 and 150 bpm.
Inputs explained
| Field | What to enter |
|---|---|
| Sex | Choose one: Male, Female |
| Do you know your VO₂ max? | Choose one: Yes, No |
| Age (years) | A number |
| Body weight | Units: kg, lb |
| Average heart rate (bpm) | A number |
| VO₂ max (ml/kg/min) | A number |
| Exercise duration | Units: min, h |
What each result means
- Per minute = [Calories burned]÷[Exercise duration]
- Estimated maximum heart rate (Tanaka) = 208 – 0.7×[Age (years)]
- Intensity (% of max HR) = [Average heart rate (bpm)]÷(208 – 0.7×[Age (years)])×100
Example values
How the main result changes when Age changes and everything else stays at the example values above:
| Age (years) | Calories burned (kcal) |
|---|---|
| 17.5 | 555.7 |
| 26.25 | 574.7 |
| 35 | 593.7 |
| 43.75 | 612.7 |
| 52.5 | 631.6 |
| 70 | 669.6 |
Formula
Men: kcal = t × (−55.0969 + 0.6309·HR + 0.1988·W + 0.2017·A) ÷ 4.184
Women: kcal = t × (−20.4022 + 0.4472·HR − 0.1263·W + 0.074·A) ÷ 4.184 (VO₂ max versions use extra terms)
Worked example
Inputs — Sex: Male; Do you know your VO₂ max?: No; Age (years): 35; Body weight: 75 kg; Average heart rate (bpm): 140; Exercise duration: 45 min.
Results — Calories burned = 593.7 kcal; Per minute = 13.19 kcal/min; Estimated maximum heart rate (Tanaka) = 184 bpm; Intensity (% of max HR) = 76.3 %.
Key terms
- VO₂ max
- Maximum rate of oxygen use, ml/kg/min.
Frequently asked questions
Is heart-rate-based estimation accurate?
Typically within about 10–15% for steady aerobic exercise.
Why does sex matter?
Body composition and heart size differ on average.
Does it work for weightlifting?
Less well – heart rate rises without proportional oxygen use.
Where does the formula come from?
Keytel et al., Journal of Sports Sciences, 2005.