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Heart Rate Zone Calculator

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Heart Rate Zone Calculator

Training zones by age.

Max heart rate

187 bpm

Zone 1 · Recovery (50–60%)

124–136 bpm

Zone 2 · Fat burn / endurance (60–70%)

136–149 bpm

Zone 3 · Aerobic (70–80%)

149–162 bpm

Zone 4 · Threshold (80–90%)

162–174 bpm

Zone 5 · Max effort (90–100%)

174–187 bpm

Uses the Tanaka formula (208 − 0.7 × age) and the Karvonen method when resting HR is given. Check with a doctor before intense training.

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