Target Heart Rate Zones & Karvonen Calculator

🔗 Open Target Heart Rate Calculator

Two common methods

The percent of max HR approach uses 220 − age as a simple max estimate. Karvonen subtracts resting HR from max to get heart rate reserve, then applies the same percentage bands—often closer to perceived effort for trained athletes.

Real max HR varies

Field tests and lab assessments beat any formula. Use zones as guides, not limits, especially if you have cardiovascular conditions—ask your clinician when in doubt.