Target Heart Rate Calculator — Karvonen Heart Rate Reserve
From age and resting heart rate, get max HR, heart rate reserve, and target HR range by intensity.
Input Data
Results
Target heart rate by intensity (Karvonen)
At a glance:Target heart rate is the recommended beating range during exercise. This calculator uses the Karvonen heart-rate-reserve method: HRR = max HR − resting HR, then target = resting + HRR × intensity%. Max HR can use 220−age or Tanaka (208 − 0.7×age).
Formula
max HR (classic) = 220 − age; max HR (Tanaka) = 208 − 0.7×age.
HRR = max HR − resting HR.
Karvonen target = resting + HRR × intensity%.
$$HR_{\text{target}} = HR_{\text{rest}} + (HR_{\text{max}} - HR_{\text{rest}}) \times I$$How to Use
- Enter age and resting HR.
- Pick the max HR formula (Tanaka is more accurate for adults).
- Set intensity band: 50–70% general, 60–75% fat-burn, 70–85% cardio.
- The tool shows the target range and zone code.
Case Studies
30yo, resting 70, classic max 190
50–70% → 70 + (190−70)×0.5 = 130 to 154 bpm.
45yo, resting 65, Tanaka max 176.5
60–75% → 65 + (176.5−65)×0.6 ≈ 132 to 149 bpm.
60yo, resting 75, classic max 160
40–60% → 75 + (160−75)×0.4 = 109 to 126 bpm.
FAQ
Why use resting HR not just max HR %?
Karvonen includes resting HR, so fitter people (lower resting) get a more personalised target even at the same age.
Is exceeding the range dangerous?
Brief overshoot is normal. If it persists with chest pain, dizziness or breathlessness, stop and see a doctor. Those with heart conditions should consult a physician before training.
How to measure resting HR?
Best just after waking: count radial pulse at the wrist for 60 seconds; average a few days.
220−age vs Tanaka?
220−age overestimates for older adults; Tanaka (208 − 0.7×age) is from a larger study and more accurate, but still an estimate. Confirm with a test.
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References
Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.