Target Heart Rate Calculator
Training heart-rate zones from 50% to 85% intensity based on your age. Add your resting heart rate to switch to the more personalized Karvonen (heart-rate-reserve) method.
Your training zones
Example: age 30, resting 60 → 70% intensity at 151 bpm (Karvonen).
What the zones mean
Intensity percentages anchor effort to your cardiovascular ceiling. At age 30 the age-predicted maximum is 190 bpm; with a resting rate of 60, the Karvonen formula puts 70% intensity at 151 bpm — computed by the same tested engine as the calculator. Lower zones build aerobic base and recovery; higher zones train speed and lactate tolerance in smaller doses.
Measuring your resting heart rate
Take it after waking, before caffeine, seated or lying quietly: count your pulse for 60 seconds (or use a tracker's overnight average). Typical adult values run 60–80 bpm, lower with aerobic fitness. Re-measure occasionally — as fitness improves, a falling resting rate nudges every Karvonen zone, which is exactly the personalization the method offers.
Frequently asked questions
How is maximum heart rate estimated?
With the classic 220 − age formula. It is a population average with real individual spread (±10–15 bpm is common), so a measured maximum from a supervised test is always better than the estimate.
What does the Karvonen method change?
Instead of taking a percentage of the maximum alone, Karvonen scales the heart-rate reserve — the gap between resting and maximum — and adds the resting rate back: THR = (max − rest) × intensity + rest. It personalizes zones to your fitness, since a lower resting heart rate shifts every zone.
Which zone should I train in?
Common practice puts easy aerobic work around 50–70% intensity and harder tempo or interval work at 70–85%. Most training plans spend the bulk of time in the easier zones. A coach or clinician can tailor this to your goals and health.
When should I be cautious with heart-rate training?
If you take heart-rate-affecting medication (such as beta blockers), have a cardiac condition, or are returning from illness, formula-based zones can be misleading — get individual guidance from a healthcare professional first.
Not medical advice: formula-based zones are general estimates and can be wrong for individuals, particularly with cardiac conditions or heart-rate-affecting medication. Consult a qualified healthcare professional before intensity-based training. Data is processed locally in your browser and never transmitted. See the methodology page.