Target Heart Rate Calculator
Calculate your maximum heart rate (Fox or Tanaka formula) and five target training zones, using plain percent-of-max or the more personalized Karvonen method.
What a target heart rate zone is
A target heart rate zone is a bpm range to stay within during exercise to hit a specific goal — warming up, burning fat, building aerobic endurance, or pushing to threshold or max effort — safely.
Step 1: maximum heart rate (HRmax)
- Fox (classic): HRmax = 220 − age
- Tanaka (more accurate for older adults): HRmax = 208 − 0.7 × age
At age 30: Fox gives 220 − 30 = 190 bpm; Tanaka gives 208 − 21 = 187 bpm.
Step 2: target zone — two methods
- Plain %HRmax: target = percent × HRmax.
- Karvonen (uses resting heart rate): target = percent × (HRmax − resting HR) + resting HR.
Worked example (Karvonen)
With HRmax = 190 and resting HR = 60, a 70% intensity target is 0.70 × (190 − 60) + 60 = 0.70 × 130 + 60 = 151 bpm.
The five zones
| Zone | % of HRmax | Purpose |
|---|---|---|
| Warm-up | 50–60% | Warm up, recovery |
| Fat burn | 60–70% | Weight management |
| Aerobic | 70–80% | Cardiovascular endurance |
| Threshold | 80–90% | Performance gains |
| Maximum | 90–100% | High intensity (short bursts) |
Common mistakes
- Forgetting to add resting HR back at the end of the Karvonen formula.
- Confusing %HRmax with %heart-rate-reserve — they give different numbers for the same person.
- Treating the formula as exact — individual variation is significant; check with a doctor for anything training-critical.
Heart rate training pairs naturally with tracking your running pace and BMI as part of an overall fitness picture.
This is a general reference tool, not medical advice. HRmax formulas are population averages and individual results vary. If you have a heart condition or other health concerns, consult a doctor before training by heart rate zones.
Frequently asked questions
- What is a target heart rate zone?
- It's a range of heartbeats per minute you aim to stay within during exercise to get a specific training effect — warm-up, fat burning, endurance, or high intensity — while training safely.
- How is max heart rate (HRmax) calculated?
- The classic Fox formula is 220 minus your age. The Tanaka formula, 208 minus 0.7 times age, is considered more accurate for older adults. Both are population averages, not exact for every individual.
- What is the Karvonen method?
- Karvonen factors in your resting heart rate, using heart rate reserve (HRmax minus resting HR): target = percent × (HRmax − resting HR) + resting HR. It personalizes zones better than plain %HRmax because fitter people tend to have a lower resting heart rate.
- What are the five heart rate zones?
- Warm-up (50–60% of HRmax), Fat burn (60–70%), Aerobic (70–80%), Threshold (80–90%), and Maximum (90–100%). Each has a different training purpose, from recovery to short high-intensity efforts.
- Why does Karvonen give a different number than plain %HRmax?
- Plain %HRmax multiplies HRmax directly, ignoring your resting heart rate. Karvonen first computes your heart rate reserve (HRmax minus resting HR) and scales that, then adds resting HR back — so two people with the same HRmax but different fitness levels get different zones.
- Is entering my resting heart rate required?
- No. Leave it blank to use simple %HRmax zones. Enter it to switch to the more personalized Karvonen method, which needs a resting heart rate below your calculated max.
- Is this a medical tool?
- No. It provides general reference estimates for training, not medical advice. If you have a heart condition or other health concerns, consult a doctor before training by heart rate zones.