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The Karvonen method personalizes your target heart rate zone by factoring in your resting heart rate, not just your age — giving fitter individuals a more accurate training range than simple age-based zones.
This calculator finds your target heart rate range using the Karvonen heart rate reserve formula.
How it works
Enter your age and resting heart rate. The calculator estimates your maximum heart rate, subtracts your resting heart rate to find your heart rate reserve, then applies a 50%–85% target intensity range to that reserve (adding back your resting rate).
- Enter age.
- Enter resting heart rate (bpm).
- Click Calculate to see your results.
Examples
Age 30, resting HR 65
A 30-year-old with a 65 bpm resting heart rate has an estimated max HR of 190 and a target training zone of 128–171 bpm using the Karvonen method.
Who should use it
- Setting a personalized cardio training intensity zone for a workout plan.
- Comparing training zones as resting heart rate improves with fitness over time.
Industry applications
- Personal training and fitness coaching
- Cardiac rehabilitation and exercise physiology
Advantages
- Personalizes the target zone using resting heart rate, not just age.
- Uses the well-established Karvonen heart rate reserve method.
Limitations
- Still relies on the "220 minus age" estimate for max heart rate, which has real individual variation.
Common mistakes to avoid
- Measuring resting heart rate after caffeine, exercise, or stress rather than at rest, which skews the whole calculation.
- Confusing this Karvonen-based target zone with the simpler percentage-of-max-HR zones from the Heart Rate Zone Calculator.
Best practices
- Measure resting heart rate consistently (e.g., every morning for a week) and use the average for the most reliable input.
Tips
- As your fitness improves and your resting heart rate drops, recalculate — the Karvonen method's target zone shifts along with it, unlike simple age-based zones.