Heart Rate Zone Calculator
Heart rate training zones define intensity ranges based on your maximum heart rate (MHR), allowing you to target specific physiological adaptations. The most common formula for estimating MHR is 220 minus age, though the Tanaka formula (208 − 0.7 × age) is more accurate for older adults. Zones are typically defined as: Zone 1 (50–60%) for active recovery; Zone 2 (60–70%) for aerobic base and fat oxidation; Zone 3 (70–80%) for aerobic threshold; Zone 4 (80–90%) for lactate threshold work; Zone 5 (90–100%) for VO₂ max intervals. The Karvonen method refines this by incorporating your resting heart rate (RHR): Heart Rate Reserve (HRR = MHR − RHR) zones account for your current fitness level and produce more personalised targets. In Australia, Garmin, Polar, and Strava all use similar 5-zone systems. Enter your age and resting heart rate to see both standard and Karvonen zones.
Frequently Asked Questions
What are the five heart rate training zones?
Zone 1 (50-60% max HR): Very light, active recovery - you can hold a conversation easily. Zone 2 (60-70%): Aerobic base building, fat burning, the foundation of endurance training. Zone 3 (70-80%): Moderate aerobic, improves cardiovascular efficiency. Zone 4 (80-90%): Hard effort, lactate threshold training - uncomfortable but sustainable. Zone 5 (90-100%): Maximum effort, develops speed and power - only sustainable for short bursts.
What heart rate zone should I train in most?
Most of your training volume should be in Zone 2. The majority of easy miles at low intensity builds your aerobic base efficiently, improves fat metabolism as a fuel source, and enhances your body's ability to transport and use oxygen. Zone 2 training should make up about 80% of your total training volume. This doesn't mean every run is easy - it means consistently building your base before adding intensity.
What is the difference between max HR and resting heart rate?
Max HR is the highest heart rate you can achieve during maximum effort - a genetic ceiling that typically declines with age. Resting HR is your heart rate at complete rest, usually measured first thing in the morning. The difference between them is called your heart rate reserve (HRR), and it's used in the Karvonen formula to calculate training zones that account for your actual fitness level rather than just your age.
Which calculation method is most accurate?
The 220 minus age formula is a population estimate and can be off by 10-15 bpm for individuals since it doesn't account for fitness level, genetics, or training history. The Karvonen method is more personalised because it uses your resting HR to calculate heart rate reserve, giving zones that reflect your actual fitness. The Maffetone method (180 minus age) is popular for endurance athletes building an aerobic base, but may be too conservative for shorter, higher-intensity events.
Is a higher max heart rate better?
A higher max HR simply means a higher ceiling - not better fitness. What matters more is how low your heart rate can go during easy efforts, which is a sign of aerobic fitness and a strong heart. How quickly your heart rate recovers after exercise is also a key indicator of cardiovascular health. Elite marathon runners often have high max HRs but exceptionally low resting and training heart rates due to their aerobic development.