Target Heart Rate Calculator
Calculate your maximum heart rate and target zones for fat burn, cardio, and peak training.
Uses the Karvonen method when resting heart rate is provided.
Target heart rate zones are calculated from your Maximum Heart Rate (MHR) and used to guide exercise intensity for specific fitness goals — fat burning, aerobic conditioning, or peak performance.
Maximum Heart Rate (MHR):
The classic formula: MHR = 220 − Age
A more accurate formula (Tanaka, 2001): MHR = 208 − (0.7 × Age)
Target Zone Formula:
Target HR = MHR × Zone Percentage
Heart Rate Reserve Method (Karvonen — more precise):
Target HR = ((MHR − Resting HR) × Zone %) + Resting HR
Worked Example — 35-year-old with resting HR of 62 bpm:
- MHR (classic): 220 − 35 = 185 bpm
- MHR (Tanaka): 208 − (0.7 × 35) = 208 − 24.5 = 183.5 bpm
Using Karvonen (MHR = 185, Resting HR = 62):
- Heart Rate Reserve (HRR) = 185 − 62 = 123 bpm
| Zone | % Range | Target HR (bpm) | Goal |
|---|---|---|---|
| Zone 1 (Recovery) | 50–60% | 123–136 | Active recovery |
| Zone 2 (Fat Burn) | 60–70% | 136–148 | Aerobic base, fat oxidation |
| Zone 3 (Aerobic) | 70–80% | 148–160 | Cardiovascular fitness |
| Zone 4 (Threshold) | 80–90% | 160–173 | Speed, lactate threshold |
| Zone 5 (Max) | 90–100% | 173–185 | Peak sprint performance |
Reference: The American Heart Association recommends exercising at 50–85% MHR for cardiovascular health. Zone 2 training (60–70%) maximizes fat oxidation and is the foundation of elite endurance training protocols.