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Weight-Loss Heart Rate Zone Calculator

Just enter your age to automatically calculate the fat-burning heart rate zone (50–70% of your maximum heart rate). Enter your resting heart rate to get a more personalized estimate with the Karvonen formula.

Input

Calculate your maximum heart rate and the fat-burning heart rate zone (about 50–70% of your maximum) from your age. Enter your resting heart rate (optional) for a more personalized estimate using the Karvonen formula.

yrs
bpm

Result

Fat-burning heart rate zone (50–70% of max heart rate)

90〜126bpm

Use this range as a guide and keep up aerobic exercise at which you can still hold a conversation for at least 20 minutes.

Max heart rate (220 − age)

180 bpm

Zone lower limit (50%)

90 bpm

Zone upper limit (70%)

126 bpm

Enter your resting heart rate to calculate a more accurate estimate with the Karvonen formula.

Exercise intensity zone guide (heart rate: bpm)

ZoneIntensityHeart rate guide
Warm-up (light exercise)40–50%72–90
Fat-burning zone50–70%90–126
Endurance (aerobic) zone70–85%126–153
High-intensity zone85–100%153–180

The fat-burning zone is an intensity at which a high proportion of fat is used for energy. To increase total calories burned, combining higher-intensity aerobic exercise and strength training is also effective.

How it works

  • Maximum heart rate is estimated with the simplified formula "220 − age". Actual maximum heart rate varies by individual, so this is only a statistical estimate.
  • The fat-burning zone is set at 50–70% intensity of your maximum heart rate (or heart rate reserve). In this range, a higher proportion of fat is used for energy, corresponding to aerobic exercise at which you can still hold a conversation.
  • When you enter your resting heart rate, the Karvonen formula (heart rate reserve method) is used. The formula is "target heart rate = (maximum heart rate − resting heart rate) × intensity + resting heart rate".
  • The exercise intensity zones are divided into four levels: warm-up (40–50%), fat burning (50–70%), endurance (70–85%) and high intensity (85–100%).
  • Exercising in the fat-burning zone uses a high proportion of fat, but total calories burned can be greater with higher-intensity exercise. To increase total calories burned, combining higher-intensity aerobic exercise and strength training is also effective.
  • The values shown are reference estimates of exercise intensity. If you have a heart condition or other chronic illness, or are about to make a major change to your exercise habits, consult a doctor or specialist.