Summary
Karvonen training zones from age and resting heart rate.
Calculation details
The 220 − age estimate is a population approximation; measured max HR can differ.
Formula
Max HR ≈ 220 − age; zone = resting + (max − resting) × intensity fraction.
Worked example
Heart-rate zones worked example
Zones span roughly 50–100% of heart-rate reserve.
How it works
Enter age and resting heart rate. Use zones as training guidance, not diagnosis — measured max HR can differ from 220 − age.
Frequently asked questions
Is this a medical diagnosis?
No. It is an educational estimate and cannot diagnose a condition or replace individualized professional advice.
Why can my actual result differ?
Estimated max HR (220 − age) often differs from a measured maximum.
When is this calculator most useful?
Use it to sketch Karvonen zones for training guidance, not diagnosis.
How are results rounded?
The calculation retains full precision; centralized display formatting rounds only the visible result.