❤️ Cardio Heart Rate Zone — Free Heart Rate Zone Calculator

Zone 1 (50–60%): Recovery. Zone 2 (60–70%): Fat burn & aerobic base. Zone 3 (70–80%): Aerobic fitness. Zone 4 (80–90%): Anaerobic/lactate threshold. Zone 5 (90–100%): Maximum effort.

Zone 2 (60–70% of max HR) burns the highest percentage of fat as fuel. It's ideal for long easy runs or cycling sessions. However, higher zones (3–4) burn more total calories per hour.

The most common estimate is 220 minus your age. For more accuracy, use the Karvonen method which factors in your resting heart rate (measured first thing in the morning).