How to use
- Enter your age.
- Optionally enter your resting heart rate, measured for a minute after waking.
- Choose a maximum heart rate formula and read your five zones.
Options explained
- Maximum heart rate
- Estimated as 220 − age, or 208 − 0.7 × age (Tanaka), which is more accurate for older adults. Individual values vary by ±10 bpm.
- Heart-rate reserve
- Target = resting + (max − resting) × intensity. It accounts for fitness, giving fitter people higher targets at the same intensity.
- Zones
- Zone 1 is 50–60% of maximum, each zone adds 10%, and zone 5 is 90–100%.
Zones at age 35
| Zone | Purpose | 220 − age (max 185) | Resting 60 (Karvonen) |
|---|---|---|---|
| 1 | Recovery | 93–111 | 123–135 |
| 2 | Endurance | 111–130 | 135–148 |
| 3 | Aerobic | 130–148 | 148–160 |
| 4 | Threshold | 148–167 | 160–173 |
| 5 | Maximum | 167–185 | 173–185 |
Frequently asked questions
Which zone burns the most fat?
Zone 2 (60–70%) uses the highest share of fat and suits long sessions, though harder efforts burn more calories in total.
Is it normal to run in zones 4 and 5?
In races and intervals, yes. Most easy runs belong in zones 2–3; living in zone 4 usually means the pace is too fast.
Do these zones apply if I take heart medication?
No. Beta blockers and similar drugs lower heart rate. Follow your doctor's guidance if you have a heart condition.
Privacy
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