Find your training heart rate zones from max and resting heart rate.
The Karvonen method personalises training zones by factoring in your resting heart rate. A fitter person typically has a lower resting HR, which gives them a larger Heart Rate Reserve (HRR). Training at the same percentage of HRR therefore represents a higher absolute HR for the fit person — matching the actual physiological demand. The Tanaka formula for max HR is more accurate than the classic 220−age across ages 18–85, particularly for trained adults.
Karvonen target heart rate
THR = (Max HR − Resting HR) × Intensity + Resting HR
Tanaka max HR
Max HR = 208 − 0.7 × Age
Heart rate zones are estimates. Maximum heart rate predictions carry ±10–12 bpm individual error. If you have a cardiovascular condition, consult your cardiologist before starting high-intensity exercise. Stop exercising and seek medical attention if you experience chest pain, dizziness or shortness of breath.
Measure immediately on waking, before getting out of bed, using a finger on your carotid or radial artery (or a wrist-based heart rate monitor). Count beats for 60 seconds. Average over 3 mornings. Stress, illness and alcohol elevate resting HR — measure on calm days.
Zone 2 (60–70% HRR) uses the highest proportion of fat as fuel because intensity is low enough for oxidative metabolism. However, higher-intensity zones burn more total calories per session, which matters more than the fat-burning percentage. Both approaches work; the best zone is the one you'll sustain consistently.
Yes — set zone alarms on your device using the bpm ranges from this calculator. Most modern GPS watches allow custom zone setup. These zones are more accurate than device defaults, which typically use only age (220−age) without your resting HR.