TOOLTrain in the right zone
Your ideal training heart rate depends on your goal — easy recovery, fat burning, endurance or peak effort. This calculator uses the Karvonen formula, which personalises your zones with your resting heart rate instead of age alone, giving ranges that actually fit you.
How the zones are calculated
Heart rate reserve (HRR) = max HR − resting HR
Target = resting HR + HRR × intensity%
Because it adds your resting heart rate back in, the Karvonen method gives higher, more individual targets than a simple percentage of max HR.
What each zone is for
- Zone 1 (50–60%) — warm-up and recovery.
- Zone 2 (60–70%) — fat burning and base endurance.
- Zone 3 (70–80%) — aerobic fitness.
- Zone 4 (80–90%) — anaerobic, faster and harder.
- Zone 5 (90–100%) — maximum effort, short intervals.
Dialling in nutrition too? Find your calories with the TDEE calculator and split them with the macro calculator.
This tool provides general estimates for educational purposes only and is not medical advice. The 220-minus-age maximum is an approximation and individual heart rates vary. Talk to a doctor before starting or intensifying exercise, especially if you have any health conditions.
Frequently asked questions
What is the Karvonen formula?
The Karvonen formula finds a target heart rate using your heart rate reserve: target = resting HR + (max HR − resting HR) × intensity. It personalises zones by accounting for your resting heart rate, not just your age.
How do you calculate maximum heart rate?
The common estimate is 220 minus your age. It's an approximation — individual maximums vary — so treat the resulting zones as guidance rather than exact limits.
What is the fat-burning heart rate zone?
The fat-burning or moderate zone is roughly 60 to 70 percent of your heart rate reserve. You burn a higher share of fat there, though higher-intensity work burns more total calories.