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Heart-rate zone calculator
Compare reserve, maximum and threshold methods with the formula visible.
Your result
Easy ceiling
143bpm
Maximum heart rate
181bpm
Your result
| Zone | Range · bpm | Share of method basis |
|---|---|---|
| Z1 | 117 - 130 | 50 - 60% |
| Z2 | 130 - 143 | 60 - 70% |
| Z3 | 143 - 156 | 70 - 80% |
| Z4 | 156 - 168 | 80 - 90% |
| Z5 | 168 - 181 | 90 - 100% |
Method and sources
HRmax = 208 - 0.7 × age · easy ceiling = HRrest + 0.70 × (HRmax - HRrest)
Tanaka: HRmax = 208 - 0.7 × age. Karvonen: HR = resting HR + share × (HRmax - resting HR); the easy ceiling here is 70% of reserve. Edwards uses 50-100% of HRmax; Friel uses a measured running threshold with the published open-ended zones. These methods are different conventions, not interchangeable physiological thresholds. Age formulas describe groups and can miss your real maximum. Gulati was derived in women. Medication, illness, heat and fatigue can change the response; use assessed values and comfortable speech to guide easy running.
Sources checked 30.10.2026
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