What Are Heart Rate Zones?
Heart rate zones are ranges of beats per minute (BPM) that correspond to different exercise intensities. Training in the right zone helps you burn fat, improve endurance, or hit peak performance — depending on your goal.
The 5 Training Zones
- Zone 1 (50–60%) — Very light. Warm-up and recovery.
- Zone 2 (60–70%) — Light. Fat-burning and base building.
- Zone 3 (70–80%) — Moderate. Aerobic conditioning.
- Zone 4 (80–90%) — Hard. Anaerobic / threshold training.
- Zone 5 (90–100%) — Maximum. Sprint / HIIT.
Karvonen Formula
Our calculator uses the Karvonen formula, which factors in your resting heart rate for more personalized zones:
Target HR = ((Max HR − Resting HR) × %Intensity) + Resting HR
Max HR is estimated as 220 − your age (or 208 − 0.7 × age for a more accurate modern formula).
Find Your Resting Heart Rate
Measure your pulse first thing in the morning, before getting out of bed — count beats for 30 seconds, then double it. A typical US adult has a resting HR of 60–100 bpm. Athletes often have 40–60 bpm.
Training Tips by Zone
- Fat loss: 60–70% of max HR for 45–60 minutes
- Cardio fitness: 70–80% for 30–45 minutes
- Performance: interval training in zones 4–5