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Karvonen Heart-Rate Zone Calculator

Estimate a training heart-rate band from age, resting pulse, and percent of heart-rate reserve.

 

 

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HRmax sketch
Low target
High target

About this calculator

Use this calculator for the Karvonen sketch: HRmax ≈ 220 − age, then target = resting HR + percent × (HRmax − resting HR). 220 − age is rough; a true max test is better.

This is not a medical clearance for exercise.

Age (years): Used only for 220 − age.

Resting HR: Pulse at true rest, in beats per minute.

Low % reserve: Lower end of the session, often around 50%.

High % reserve: Upper end, often around 85%.

HRmax sketch: 220 − age.

Low target: Lower training pulse.

High target: Upper training pulse.