AbraCalc

Karvonen Target Heart Rate: Age 25, RHR 55, 80% Intensity

A 25-year-old with a resting heart rate of 55 bpm training at 80% intensity has a target heart rate of approximately 172 bpm.

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  1. Enter age, resting heart rate and training intensity in the fields above.
  2. Results update instantly as you type — or click Calculate.
  3. Read your target heart rate and the full breakdown beneath it.

Calculate your high-intensity training zone heart rate using the Karvonen formula at age 25.

Frequently asked questions

What is heart rate reserve?
HRR = Maximum HR − Resting HR. It represents the range of heart rates available for exercise. A higher HRR (lower resting HR) generally indicates better cardiovascular fitness.
How is this different from the simple percentage method?
Simple method: THR = MHR × intensity%. Karvonen: THR = (MHR − RHR) × intensity% + RHR. Karvonen gives higher target HRs at the same percentage because it accounts for resting heart rate.