Heart Rate Zones Calculator
Calculate training zones with the Karvonen heart-rate reserve method.
Advanced inputs+
How this works
Uses the Karvonen heart-rate reserve method: resting heart rate plus a percentage of max heart rate minus resting heart rate.
Medical disclaimer
Educational tool only — not medical advice. Consult a qualified provider.
Frequently asked questions
What does the Heart Rate Zones Calculator estimate?+
It estimates training heart-rate ranges from age and resting heart rate. The result is a planning estimate, not a diagnosis or personal medical advice.
How accurate is this heart rate zones result?+
Accuracy depends on the inputs and the limits of the formula. Use the result as a reference point and compare it with real-world outcomes over time.
Can I share my result?+
Yes. Change the inputs, use the copy-link button, and the current values are preserved in the URL for reopening or sharing.
Will my last input be remembered?+
Yes. The calculator saves the latest inputs in this browser so a reload can restore the most recent values.
Should I use this for medical decisions?+
No. These calculators are educational tools. Talk with a qualified clinician before making health, pregnancy, nutrition, or training decisions.