- Fox: MaxHR = 220 − age
- Tanaka: MaxHR = 208 − 0.7×age
- Gellish: MaxHR = 207 − 0.7×age
- Nes: MaxHR = 211 − 0.64×age
- Gulati: MaxHR = 206 − 0.88×age
Two approaches are supported. Both create a bpm range for each zone.
- Percent of Max HR: TargetHR = MaxHR × intensity%
- Karvonen (HRR): TargetHR = (MaxHR − RestHR) × intensity% + RestHR
- Enter your age and select sex for context.
- Optionally enter your resting heart rate for HRR zones.
- Choose an equation. Tanaka is a solid default.
- Select zone method and zone model, then press Submit.
- Review the results above the form and adjust intensity.
- Use CSV or PDF export to save your plan.
| Age | Estimated Max HR (bpm) | Zone 2 (60–70%) | Zone 4 (80–90%) | Notes |
|---|---|---|---|---|
| 20 | 194 | 116–136 | 155–175 | General fitness |
| 35 | 184 | 110–129 | 147–166 | Steady running |
| 50 | 173 | 104–121 | 138–156 | Cycling base |
| 65 | 163 | 98–114 | 130–147 | Brisk walking |
Why maximum heart rate matters
Maximum heart rate is a reference point for setting effort levels. When you anchor sessions to a percentage of your estimated peak, you can standardize easy runs, tempo work, and interval days across weeks. The output helps compare workouts even when pace, terrain, or fatigue changes. Most adults see day‑to‑day variation of a few beats per minute, so use ranges rather than a single value. Pair heart rate with perceived exertion to confirm the day’s intensity today.
Selecting an estimation equation
Different equations reflect different study groups and ages. The classic 220 − age is simple but can be off for many people. Tanaka (208 − 0.7×age) often tracks better for general fitness planning, while Gelish may suit some recreational athletes. If you have a lab or field test value, treat that measured result as your primary reference and use the calculator for zone math. For older athletes, expect slightly lower peaks and rely on consistent zone ranges.
Reading zone targets with real training
Zone models translate your estimate into actionable intensity bands. Zone 2 typically supports aerobic base and recovery, Zone 3 improves sustainable endurance, and Zones 4–5 prioritize threshold and high‑intensity capacity. For steady sessions, aim for the middle of the band. For intervals, hit the lower end early, then stabilize as breathing and rhythm settle.
Using resting heart rate for HRR zones
Heart‑rate reserve (Karvonen) adds personal context by accounting for resting heart rate. Two people can share the same max estimate but have different resting values, which changes training targets. Measure resting heart rate after waking, before caffeine, for three mornings, then use the average. HRR zones are often preferred for beginners returning after a break.
Quality, safety, and ongoing adjustments
Wearable sensors can lag during fast changes, especially on wrist devices. If readings jump or drop, tighten the strap, warm up longer, or switch to a chest strap for interval work. Recheck your inputs every 8–12 weeks, and adjust zones if your easy efforts feel too hard or if you consistently exceed your targets. Stop exercise and seek help if you feel chest pain, dizziness, or unusual shortness of breath.
No. Maximum heart rate is an estimated ceiling. Target heart rate is a training range, usually a percentage of your maximum or heart‑rate reserve, used to guide specific workout intensities.
Tanaka is a reliable default for many adults. Use measured test results when available. If a formula feels consistently too easy or too hard, keep the same equation and adjust your training zones gradually.
Optical wrist sensors can lag, especially during intervals, cold weather, or loose fit. Motion, sweat, and skin tone can affect readings. A chest strap usually tracks changes faster and improves accuracy.
Resting heart rate is optional. If you provide it, HRR zones can better reflect individual fitness differences. If you do not know it, use percent‑of‑max zones and focus on comfortable, repeatable effort.
It typically changes little with training and often declines slowly with age. Fitness improvements usually show up as lower heart rate at the same pace, quicker recovery, and a higher sustainable intensity.
Review every 8–12 weeks or after a major change in training volume, weight, or health. Keep comparisons consistent by using the same equation and zone model, then update only when patterns persist.