Heart Rate Zones Calculator
Training heart rate zones using the Karvonen method.
years
bpm
How it works
Max heart rate is estimated as 220 − age. The Karvonen method adds a percentage of your heart rate reserve (max − resting) to your resting rate. The 220 − age formula can be off by 10 bpm or more, so a measured max from a hard test is better. Example: with the default values, max heart rate is 185 bpm and Zone 2 runs 135–148 bpm.
FAQ
Is this calculator free?
Yes. No signup is needed and nothing you enter is stored.
Is the result exact?
Results are rounded for display. For financial, medical, or legal decisions, confirm with a professional.
Do my numbers leave my device?
No. The calculation runs in your browser.