Heart Rate Zone Calculator
Estimate maximum heart rate and five zones for training — choose standard, Tanaka, or Karvonen (optional resting HR). Formula-based estimates vary by individual.
Inputs
Zones (BPM)
Estimated MHR: — bpm
Why zones matter
Heart rate is a practical proxy for intensity. Zone 2 is often used for easy aerobic base building; zone 4–5 for short intervals and VO₂ stimulus. The old “fat-burning zone” is a partial truth — you burn a higher proportion of fat at lower intensities, but total calorie burn and overall deficit matter more for body composition.
Measure resting HR on waking for consistency. HRV (heart rate variability) is increasingly used for recovery — consumer devices vary in accuracy. Karvonen personalizes zones when resting HR is known; Tanaka is often closer for older adults than 220−age.
Pair with Calorie / TDEE, BMI, and Body Fat for a broader fitness picture — not medical diagnosis.