Heart Rate Zone Calculator
Estimate five heart rate training zones for recovery, endurance, tempo, threshold, and high-intensity work using your age and optional resting heart rate.
Heart Rate Zone Calculator
Medical Disclaimer: Max heart rate from 220 − age is an estimate. Individual max HR varies; use perceived effort or lab testing when precision matters.
How this is calculated
Formula: Estimated maximum heart rate or Karvonen heart-rate reserve zones
The calculator first estimates maximum heart rate from age using the selected formula. Any age-based equation describes a population average and may differ substantially from your measured maximum.
With a resting heart rate, the Karvonen method calculates heart-rate reserve—the difference between maximum and resting heart rate—and applies each intensity percentage to that reserve.
The five displayed bands are practical training estimates. Medication, heat, altitude, fatigue, illness, and device accuracy can all change the heart rate seen at a given effort.
Five-zone training overview
| Zone | Typical effort | Common purpose |
|---|---|---|
| Zone 1 | Very easy | Warm-up, cool-down, and light recovery |
| Zone 2 | Easy–moderate | Aerobic endurance and comfortable steady work |
| Zone 3 | Moderate–hard | Tempo and sustained aerobic conditioning |
| Zone 4 | Hard | Threshold-focused intervals |
| Zone 5 | Very hard | Short high-intensity efforts with recovery |
Train with zones safely
Use heart rate alongside perceived effort and the talk test. A zone is a guide for session intent, not a score that must be reached regardless of how you feel.
Tips
- •Measure resting heart rate after waking on several calm mornings and use the average.
- •Allow heart rate to rise gradually during intervals; it can lag behind a sudden increase in effort.
- •Chest straps are often more responsive than wrist sensors during rapid or irregular movement.
- •Stop exercise and seek medical care for chest pain, fainting, severe breathlessness, or other concerning symptoms.
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Frequently asked questions
Zones are percentages of estimated maximum heart rate or, with the Karvonen method, percentages of heart-rate reserve added back to resting heart rate. The latter incorporates individual resting pulse.
Heart rate zones are estimates for general education and are not medical advice, diagnosis, or clearance to exercise. Consult a healthcare professional before changing activity if you have cardiovascular risk, symptoms, a medical condition, or take heart-rate-altering medication.
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