Find your maximum heart rate and five training zones from your age. Add your resting heart rate for personalised Karvonen zones.
Maximum heart rate uses the common 220 minus age estimate. If you enter your resting heart rate, the zones use the Karvonen heart-rate-reserve method, which is more personalised. Zones are a guide; a lab test gives your true maximum.
This tool uses the well-known estimate of 220 minus your age. It is a population average, so your real maximum can be 10 to 15 beats higher or lower. Only a supervised maximal test measures it exactly.
Karvonen sets zones using your heart-rate reserve, the gap between your resting and maximum heart rate. It is more personalised than plain percentages, so entering your resting heart rate gives more accurate zones, especially if you are very fit.
Each zone targets a different adaptation. Lower zones build endurance and aid recovery, the middle zone develops aerobic fitness, and the top zones improve threshold and peak performance. Most training should sit in the lower zones.