Cardio Cardio Heart Rate Endurance

Heart Rate Zone Calculator

🧮 About this calculator

Calculates heart-rate training zones using the Karvonen formula (which factors in resting HR for better accuracy at the lower zones).

Inputs
📘 Formula & explanation
Karvonen: Target HR = ((HRmax - HRrest) * %intensity) + HRrest, where HRmax = 220 - age

The Karvonen formula uses heart rate reserve (HRR = HRmax - HRrest) and adds resting HR back, giving a more accurate zone calculation than the simpler 'percentage of HRmax' method.

Related calculators

Keep calculating

Apply this to your training

Use the result to pick or adjust a workout plan, or browse the exercise library.

Browse workout plans Browse exercises