Heart-rate zones turn "do some cardio" into a precise instruction. Each zone trains a different system in your body.
Calculate your zones
Heart Rate Zone Calculator
Open full tool →187bpm
Max heart rate · Karvonen
- 1Recovery129–140
- 2Fat burn / Endurance140–152
- 3Aerobic / Tempo152–164
- 4Threshold164–175
- 5Max effort175–187
What each zone does
| Zone | % of max HR | Feels like | Use it for |
|---|---|---|---|
| 1 | 50–60% | Very easy | Warm-up, recovery |
| 2 | 60–70% | Can hold a conversation | Aerobic base, fat oxidation |
| 3 | 70–80% | Talking gets hard | Tempo work |
| 4 | 80–90% | A few words at a time | Improving VO₂max |
| 5 | 90–100% | All-out | Short sprints |
A simple weekly split
- 2–3 sessions of zone 2, 30–45 minutes (incline walk, cycle, cross-trainer).
- 1 session of intervals: 6 × 1 minute in zone 4–5 with 2 minutes easy between.
Quick quiz
Which zone lets you comfortably hold a conversation?
If you're taking blood-pressure or heart medication, zone formulas may not apply — speak to your doctor first.
