Heart Rate Zone Calculator: Compare Max Heart Rate Formulas

Age-based formulas are commonly used to estimate maximum heart rate, but different formulas give different results and can disagree substantially with measured values.2,7 This calculator shows the common formulas side by side, how far apart they are for your age, and the zones they produce. A valid measured maximum replaces the estimate.7

Age
Measured max HR (optional)
Resting HR (optional)
Sex

Which formula is best?

None can reliably predict the exact maximum heart rate of an individual.7 The Tanaka formula (208 − 0.7 × age) comes from a meta-analysis of 351 studies and 18,712 people; in a separate study of 99 exercise tests, all nine age equations tested showed wide limits of agreement with measured maximum heart rate.8,9 The spread between formulas is a useful reminder of that uncertainty.

Better anchors than age

Zones anchored to individually measured thresholds (lactate or ventilatory) can separate easy from hard training better than generic percentages, although the evidence is stronger for some thresholds than others.5 “Zone 2” is not one universally defined intensity: its meaning differs between three-zone and five-zone models.10,11

References

Every figure and statement in this tool is linked to a source: the original study where my article cites one, otherwise my own article on the topic. The small numbers in the text refer to this list.

  1. Tanaka et al. 2001. Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology.
  2. Martin et al. 2025. Exploratory analysis of the accuracy of age-based maximal heart rate equations across cardiorespiratory fitness levels. PLoS One.
  3. Gulati et al. 2010. Heart Rate Response to Exercise Stress Testing in Asymptomatic Women. Circulation.
  4. Sarzynski et al. 2013. Measured maximal heart rates compared to commonly used age‐based prediction equations in the heritage family study. American Journal of Human Biology.
  5. Dr. Antti Rintanen: Heart Rate Zones: What the Research Actually Shows About Training by Heart Rate
  6. IANNETTA et al. 2020. A Critical Evaluation of Current Methods for Exercise Prescription in Women and Men. Medicine and Science in Sports and Exercise.
  7. Dr. Antti Rintanen: Max Heart Rate and Age: What the Research Actually Shows
  8. Tanaka et al. 2001. Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology.
  9. Shookster et al. 2020. Accuracy of Commonly Used Age-Predicted Maximal Heart Rate Equations. Int J Exerc Sci.
  10. Meixner et al. 2025. Zone 2 Intensity: A Critical Comparison of Individual Variability in Different Submaximal Exercise Intensity Boundaries. Translational Sports Medicine.
  11. Seiler and Kjerland 2004. Quantifying training intensity distribution in elite endurance athletes: is there evidence for an “optimal” distribution?. Scandinavian Journal of Medicine and Science in Sports.

Sources

This tool is based on the articles below and the studies cited in them:

This tool is for general education. It does not interpret your own results, give personal recommendations or replace an assessment by your doctor.