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Heart Rate Zone Calculator

Calculate your 5 training heart-rate zones with the Karvonen heart-rate reserve method, using your age and resting heart rate.

By Health Fitness Hub Editorial TeamLast reviewed May 6, 2026
Your numbersAgeyrsSexWeightHeightActivity
Zone 2 rangeHeart Rate Zone Calculator
135-148bpm
Zone 1
123-135 bpm
Zone 2
135-148 bpm
Zone 3
148-160 bpm
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 are heart rate training zones?+

Heart rate zones are percentage bands of your heart-rate reserve (max heart rate minus resting heart rate) used to guide training intensity. The five common zones run from Zone 1 (very easy recovery, about 50-60%) through Zone 5 (maximum effort, about 90-100%). Zone 2 builds aerobic base, while Zones 4-5 develop speed and threshold. This is general fitness information, not medical advice.

What does the Heart Rate Zone 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.

Related tools

What are heart rate training zones?

Heart rate zones are percentage bands of your heart-rate reserve — your maximum heart rate minus your resting heart rate — used to guide how hard you train. The five common zones run from Zone 1 (very easy recovery, about 50-60%) up to Zone 5 (maximum effort, about 90-100%).

Zone 2 builds your aerobic base and is where most easy endurance work happens, while Zones 4-5 develop speed and lactate threshold. This calculator uses the Karvonen heart-rate-reserve method; pair it with the running pace calculator to match effort to pace. This is general fitness information, not medical advice.