Compare percentage-of-maximum and heart-rate-reserve estimates using age, optional measured maximum, and resting heart rate.
Calculate with the Heart Rate Zone Calculator
Enter the details below. Your values stay in this browser and are validated before results are shown.
Heart Rate Zone Calculator results
How to use the Heart Rate Zone Calculator
- Select the requested method and unit system where available.
- Enter measured values carefully using the labels and active units.
- Select Calculate or press Enter.
- Read the estimate together with its method, assumptions, limitations, and safety notice.
Worked example
At age 40, 220 − age estimates a maximum of 180 bpm; 50%–70% gives roughly 90–126 bpm.
Interpreting the estimate
Zones are estimates for exercise planning and do not measure fitness or diagnose a condition.
Limitations
- Medication, heat, illness, fitness level, and heart conditions can alter heart-rate response.
- The 220 − age maximum estimate can differ substantially from an individual maximum.
Frequently asked questions
What is the Karvonen method?
It applies the intensity percentage to the difference between maximum and resting heart rate, then adds resting heart rate back.
Is the heart-rate calculator a medical assessment?
No. It provides an educational estimate from the values entered and cannot account for every individual or clinical factor.
Does CalculatorCheck store my health information?
No. The calculation runs in your browser, and the entered values are not sent to a server or added to the page URL.