This calculator is for informational purposes only and does not constitute medical advice. Results are estimates based on general formulas. Consult a qualified healthcare professional before making health decisions.
Target Heart Rate Calculator
Optimize your training with personalized heart rate zones.
Your Details
Used to estimate Max Heart Rate (220 - Age).
Optional. Improves accuracy (Karvonen formula).
Using Standard Formula. Enter Resting HR for better accuracy.
Training Zones
Heart rate zones translate cardiovascular training intensity into something you can actually monitor mid-workout. The five-zone model separates easy aerobic work from threshold sessions and maximal efforts — different zones produce different physiological adaptations.
Calculating max HR and the five zones
Max HR estimates: 220 − age (simple) or 211 − 0.64 × age (Tanaka, more accurate). Zones as % of max: Zone 1 (recovery) 50-60%, Zone 2 (aerobic) 60-70%, Zone 3 (tempo) 70-80%, Zone 4 (threshold) 80-90%, Zone 5 (VO2max) 90-100%. The Karvonen method uses heart rate reserve (HRR = max HR − resting HR) for individuals with notably high or low resting HR.
When to use this calculator
Use it to plan endurance training. Most well-designed endurance programs spend 80% of time in Zone 2 — the conversational pace that builds aerobic base and mitochondrial density — and 20% in Zones 4-5. Use the calculator to find your specific BPM ranges, then train inside them rather than going by perceived effort alone.
Worked example
A 35-year-old with a resting HR of 60. Tanaka max HR: 211 − 0.64 × 35 = 188 bpm. Zone 2 (60-70%): 113-132 bpm. Zone 4 (80-90%): 150-169 bpm. Karvonen Zone 2 with HRR: ((188 − 60) × 0.65) + 60 = 143 bpm midpoint, slightly higher than the simple % method — typical for fit individuals.