Fat Burning Zone Calculator — Heart Rate for Fat Loss
The fat-burning zone is the heart rate range (60–70% of your maximum) where fat is the primary energy source. Enter your age to find the zone in beats per minute, plus all five training zones, using your choice of max HR formula.
years
Max HR formula
bpm
Lower bound of fat-burning zone (60–70% of max HR). Upper bound: 133 bpm
- 1
Maximum heart rate
220 − 30 = 190 - 2
Fat-burning lower bound (60%)
190 × 0.60 = 114
How does this calculator work?
Fat-burning zone = 60–70% of Max HR. Using Max HR = 220 − age (or Tanaka/Gellish for older adults): a 35-year-old has Max HR ≈ 185 bpm and a fat-burning zone of 111–130 bpm. The Karvonen method refines this using resting heart rate. Fat burns efficiently here, but total calorie burn is higher at greater intensities.
Formula
How this is calculated
Your maximum heart rate (Max HR) is the highest beats per minute your heart can sustain during all-out exertion. The simplest estimate is the classic Haskell–Fox formula: Max HR = 220 − age. The Tanaka formula (208 − 0.7 × age) and Gellish formula (207 − 0.7 × age) are derived from larger studies and tend to be more accurate for older adults, giving slightly higher values above age 40.
The fat-burning zone is defined as 60–70% of Max HR. At this moderate intensity, the body relies primarily on aerobic fat oxidation for fuel — fat supplies a higher percentage of total calories than at higher intensities. However, total calorie burn per minute is lower than at higher intensities, so higher zones burn more total calories per session. Both moderate and high intensity exercise support fat loss; the "fat-burning zone" is most useful for long, sustainable sessions and active recovery.
The Karvonen (heart-rate reserve) method accounts for resting heart rate, giving a personalized target that reflects your cardiovascular fitness level. HRR = Max HR − resting HR; Karvonen target = resting HR + HRR × intensity. This method gives slightly higher absolute heart rates for fitter individuals (lower resting HR) because their heart-rate reserve is larger.
Frequently asked questions
The fat-burning zone maximises the fraction of calories from fat per minute, but higher-intensity zones burn more total calories per session and boost post-exercise oxygen consumption. A mix of intensities is most effective for overall fat loss.
The Haskell–Fox (220 − age) formula is the most familiar. If you are over 40, the Tanaka or Gellish formula tends to give a more accurate estimate. All three have individual error of ±10–15 bpm; a stress test measures your actual maximum.
The Karvonen formula uses your heart-rate reserve (max HR minus resting HR) to personalise target zones. It accounts for fitness level — two people of the same age but different resting heart rates will have different Karvonen targets.
Also known as
TG we-Calculate Editorial Team. (2026). Fat Burning Zone Calculator — Heart Rate for Fat Loss [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/fat-burning-zone-calculator
TG we-Calculate Editorial Team. "Fat Burning Zone Calculator — Heart Rate for Fat Loss." TG we-Calculate. 2026. https://we-calculate.com/calculator/fat-burning-zone-calculator.
TG we-Calculate Editorial Team, "Fat Burning Zone Calculator — Heart Rate for Fat Loss," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/fat-burning-zone-calculator
@misc{wecalculate_fat_burning_zone_calculator, title = {Fat Burning Zone Calculator — Heart Rate for Fat Loss}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/fat-burning-zone-calculator}}, year = {2026}, note = {TG we-Calculate} }
Did this calculator help you?