Free heart rate zone calculator finds your five training zones from age and resting heart rate using the Karvonen formula for fat burn and cardio.
Heart rate zones are intensity ranges that help you train the right energy system. Zone 1 is easy recovery, Zone 2 builds aerobic endurance and is the classic fat-burn zone, Zone 3 improves general cardio fitness, Zone 4 raises your lactate threshold, and Zone 5 is short maximum effort.
The calculator offers two methods. The Tanaka method estimates your maximum heart rate from age alone. The Karvonen method (heart-rate reserve) also uses your resting heart rate, which makes the zones more personal and accurate for most people.
Choose a method, set your age and resting heart rate, and you will see your max heart rate plus the bpm range for each of the five zones. Zone 2 is labeled as the fat-burn range.
Set the values and the zones update instantly.
Zone 1 (50-60%) is easy recovery, Zone 2 (60-70%) is the fat-burn endurance zone, Zone 3 (70-80%) builds aerobic cardio fitness, Zone 4 (80-90%) is threshold training, and Zone 5 (90-100%) is maximum effort. Each zone trains a different energy system.
Tanaka estimates your maximum heart rate from age (208 - 0.7 x age) and applies zone percentages to that number. Karvonen also subtracts your resting heart rate, so the zones are personalized to your fitness; fitter people with lower resting heart rates get more accurate zones.
Zone 2 (60-70%) uses fat as the main fuel and is often called the fat-burn zone. However, total calories burned matter more for weight loss; higher-intensity work burns more total calories per minute, and Zone 2 still builds the endurance base.
The 220 minus age formula is just an average and often inaccurate. Tanaka 208 - 0.7 x age is a better estimate, and even then individual maximum heart rates vary by about 10-20 bpm. The only exact way is a supervised maximal exercise test.
Take it first thing in the morning before getting out of bed, while lying still. Count beats for 30 seconds and multiply by 2, or use a heart-rate monitor. Average three mornings for a stable value.
Yes. Training mostly in Zone 2 builds the aerobic base safely and comfortably, and keeping most runs easy reduces injury risk. As fitness improves, your resting heart rate typically drops and your zones shift.