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Fitness

❤️ Heart Rate Zone Calculator

Calculate your 5 heart rate training zones using the Karvonen method for optimised training.

❤️ Karvonen Method

Max HR

208 − 0.7 × age

Tanaka formula

Target HR

HRR × %intensity + resting HR

Heart Rate Reserve method

The Karvonen method uses Heart Rate Reserve (max HR − resting HR) for personalised zones, accounting for baseline fitness.

🎯 The 5 Zones

Zone 1 (50–60%)Recovery
Zone 2 (60–70%)Fat burning / base
Zone 3 (70–80%)Aerobic / tempo
Zone 4 (80–90%)Threshold
Zone 5 (90–100%)VO2 max / sprint

💡 Training Tips

  • 80% of training in Zones 1–2
  • Zone 2 builds aerobic base
  • Zone 4 improves threshold
  • Zone 5 sparingly for VO2 max
  • Monitor morning resting HR

Why HR Training Works

Training by heart rate ensures correct intensity. Many athletes train too hard on easy days and too easy on hard days.

The 80/20 Rule

Elite athletes spend ~80% in Zones 1–2 and only 20% in Zones 3–5. This polarised model outperforms moderate-intensity training.

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