Maximum heart rate and all training zones by age
Training by heart rate zones has been a staple of endurance sports coaching since the 1970s, when researchers began mapping exercise intensity to percentages of an athlete's maximum heart rate rather than pace or perceived effort alone. Splitting effort into named zones — from a light warm-up pace to an all-out sprint — gives runners, cyclists and gym-goers a simple, heart-rate-based way to judge how hard a session actually is, independent of terrain, weather or fitness level.
Each zone serves a different training purpose. The lower zones build aerobic endurance and burn a higher proportion of fat as fuel, the middle zones improve cardiovascular fitness and lactate threshold, and the top zone develops maximum aerobic capacity and sprint power — the reason interval workouts alternate between zones rather than holding one pace throughout a session.
A heart rate monitor and a lab test remain the most accurate way to find your true zones, but the age-based formula used here gives a quick, no-equipment estimate that's close enough for everyday training decisions. This calculator runs entirely in your browser, so you can check your zones instantly before a workout without creating an account or wearing any hardware.