FREE RUNNING TOOLS
Heart-rate zone calculator
Compare percentage-of-maximum and heart-rate-reserve zones using your own heart-rate values.
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Example result
| Zone | Percentage band | Heart rate (bpm) |
|---|---|---|
| Zone 1 | 50–60% | 120–133 |
| Zone 2 | 60–70% | 134–147 |
| Zone 3 | 70–80% | 148–161 |
| Zone 4 | 80–90% | 162–175 |
| Zone 5 | 90–100% | 176–190 |
How it works
Percentage of maximum uses maximum × intensity. Heart-rate reserve uses resting + (maximum − resting) × intensity. This tool uses five 10-percentage-point bands from 50% to 100%. Integer bpm ranges do not overlap: the upper boundary belongs to the next band, except 100%. These are calculation conventions, not measured physiological thresholds.
Use a reliable maximum if you have one. Age equations estimate population averages; this calculator does not measure your maximum or prescribe training intensity.
Worked example
With a maximum of 190 bpm and resting heart rate of 50 bpm, reserve is 140 bpm. The 60% boundary is 50 + 140 × 0.60 = 134 bpm; 70% is 148 bpm. The second band therefore shows 134–147 bpm. Percentage-of-maximum gives 114–132 bpm for the same band.