Heart Rate Zone Calculator (Max HR, Karvonen)
Heart rate zone calculator: maximum heart rate by age and five training zones with the Karvonen (heart rate reserve) method.
HR = HRrest + % · (HRmax − HRrest)
How to use this calculator
- Type your input in the box.
- The result updates as you type.
- Use “Copy result” or “Copy link” to share it.
Max HR ≈ 208 − 0.7 × age (Tanaka), more accurate than 220 − age for adults over 40.
Karvonen zones use your resting pulse: HR = rest + % × (max − rest).
For general information only; it does not replace advice from a doctor or other health professional.
Frequently asked questions
Max heart rate at 40?
About 180 bpm (Tanaka).