Fat Burning Zone Calculator

Calculate your fat burning heart rate zone, typically 60-70% of maximum heart rate. We use gender-specific formulas (Tanaka for men, Gulati for women) for more accurate results. Enter your details to find your personalized Zone 2 range.

Your Fat Burning Zone

Zone 2 · 60–70% of Max HR

Disclaimer: This calculator is for informational purposes only and does not provide medical advice. Always consult with a healthcare professional before starting any new exercise program.

Key Takeaways

60–70% of Max HR
The classic fat-burning zone — high fat percentage, moderate calorie burn.
% fat ≠ total fat
Higher intensity burns more total fat calories per minute — despite a lower fat %.
Best for long sessions
45–90 min steady-state is where Zone 2 shines.
Women oxidize more fat
That's why we use the Gulati formula for female users.
Trains mitochondria
Mitochondrial density and fat-oxidation enzymes upregulate here — not in Zone 4.
Diet still decides fat loss
Total energy balance beats zone selection every time.

The Fat Burning Zone: Fact vs. Myth

Bottom line
Fat burning zone = higher share of fat, not necessarily more fat lost. Use it for volume and base; rely on total energy balance for fat loss.

Go Deeper: Training Guides

Zone 2 doesn't exist in isolation. These guides explain how it fits into a complete training structure.

Zone 2 Complete Guide

Mitochondria, fat oxidation, and how to calculate your exact Zone 2 range by age.

80/20 Polarized Training

Dr. Seiler's research shows 80% of training should be in Zone 2. Learn why — and how to apply it.

Karvonen Method Explained

More accurate zone calculation using your resting heart rate — ideal for Zone 2 precision.

Fat Burning Zone by Age

Your fat burning zone changes as you age because your maximum heart rate decreases. Here are typical Zone 2 ranges for different age groups:

Fat Burning Zone for 25-Year-Olds

Men: 117-137 bpm | Women: 110-128 bpm

At this age, you can sustain higher intensities while still primarily burning fat.

Fat Burning Zone for 35-Year-Olds

Men: 111-130 bpm | Women: 105-123 bpm

Optimal zone for building endurance base while maintaining fat oxidation.

Fat Burning Zone for 45-Year-Olds

Men: 105-123 bpm | Women: 100-117 bpm

Focus on consistency in this zone for cardiovascular health and weight management.

Fat Burning Zone for 55-Year-Olds

Men: 99-116 bpm | Women: 95-111 bpm

Prioritize Zone 2 training for heart health, longevity, and metabolic efficiency.

How to Train in the Fat Burning Zone

Fat Burning Zone Walking

Brisk walking is an excellent way to stay in Zone 2. For most adults, walking at 3.5-4.5 mph on flat terrain will keep you in the fat burning zone. This makes it an accessible option for beginners and those recovering from injury.

  • • Duration: 30-60 minutes for optimal fat oxidation
  • • Frequency: 4-6 days per week for weight management
  • • Tip: Add incline (2-4%) to increase intensity while maintaining Zone 2

Fat Burning Zone Running

Easy, conversational-pace running is the classic Zone 2 workout for runners. If you can't speak in complete sentences, you're running too fast for the fat burning zone.

  • • Pace: Typically 60-90 seconds per mile slower than race pace
  • • Duration: 45-90 minutes for endurance building
  • • Breathing: Should be controlled, able to breathe through nose

Fat Burning Zone Cycling

Cycling is particularly effective for Zone 2 training because the lower impact allows for longer sessions. Your cycling heart rate may differ from running at the same perceived effort; the difference varies between individuals, so a fixed bpm adjustment is not a reliable way to convert running zones to cycling zones.

  • • Duration: 1-3 hours for serious endurance building
  • • Cadence: 85-95 RPM for optimal efficiency
  • • Terrain: Flat to moderate hills to maintain steady heart rate

Scientific Evidence for Zone 2 Training

Mitochondrial Benefits

Endurance-training research associates sustained Zone 2 volume with improved mitochondrial density and fat oxidation. Mitochondria are the "powerhouses" of your cells that convert fat and carbohydrates into energy. More mitochondria means better fat oxidation capacity, even at rest.

Lactate Clearance

Zone 2 training improves your body's ability to clear lactate at lower intensities. This means you can sustain higher workloads before fatigue sets in—beneficial for both everyday activities and athletic performance.

Metabolic Health

Regular Zone 2 training has been linked to improved insulin sensitivity, better blood lipid profiles, and reduced risk of metabolic syndrome. It's a cornerstone of cardiovascular health across all age groups.

What should I actually do?

Calculate all 5 zones
See your full HR profile — not just the fat-burning band.
Deep dive: Zone 2 guide
Mitochondria, fat oxidation, exact ranges by age.
Zone 2 and fat loss — the truth
What the science actually says about losing weight.
Build an 80/20 week
How to combine easy fat-burning volume with hard sessions.
Fat-burning workouts for belly (2026)
4-week protocol + app comparison.
Karvonen for precision
Refine your zone with resting HR.

Fat Burning Zone Calculator

Find your personal fat-burning heart rate zone (60–70% of HRmax). Zone 2 is where the highest percentage of calories comes from fat oxidation.

Quick Answer: What is the fat-burning heart rate zone?

The so-called fat-burning zone is a training-zone label, commonly estimated at 60–70% of maximum heart rate (Zone 2). It does not mean the body only burns fat in this range: fat and carbohydrate are used at every intensity, and this band simply has the highest percentage of energy coming from fat. For a 50-year-old man (estimated HRmax ≈ 173 bpm, Tanaka) that is about 104–121 bpm; for a 50-year-old woman (estimated HRmax ≈ 162 bpm, Gulati) about 97–113 bpm. Higher intensities burn more total calories per minute, and long-term fat loss depends on weekly energy balance rather than on training inside any single zone.

Estimated Zone 2 (easy aerobic) at 60–70% of estimated maximum heart rate, by age. Men use Tanaka (208 − 0.7 × age); women use Gulati (206 − 0.88 × age). Values are population estimates, not measured maximums.
Age Est. HRmax, men (Tanaka) Zone 2 (easy aerobic) bpm, men Est. HRmax, women (Gulati) Zone 2 (easy aerobic) bpm, women
20194116–136188113–132
25191115–134184110–129
30187112–131180108–126
35184110–129175105–123
40180108–126171103–120
45177106–124166100–116
50173104–12116297–113
55170102–11915895–111
60166100–11615392–107
6516398–11414989–104
7015995–11114486–101

Why the men's and women's columns differ: the zone percentages are identical for both — 60–70% of HRmax is Zone 2 regardless of sex. Only the equation used to estimate HRmax differs: Tanaka (208 − 0.7 × age) is used for men and Gulati (206 − 0.88 × age), derived from a study of 5,437 women, is used for women. Because Gulati declines faster with age, the two estimates are close in the twenties and diverge by roughly 10 bpm by age 60. That gap reflects the study population each equation came from, not a different physiological zone model — and individual variation (±10–12 bpm) is larger than the difference between the formulas.

How to read these numbers: they are estimated maximum heart rates from age-based equations, not measured maximums. Individual HRmax varies by roughly ±10–12 bpm around any age prediction, so treat the bands as a starting range and adjust using perceived effort or a supervised maximum-effort test. Percent-of-HRmax zones are used here; Karvonen (heart-rate-reserve) zones are only shown once you enter a known resting heart rate.

Method: percentage of estimated HRmax. Formulas: Tanaka et al. 2001 (men), Gulati et al. 2010 (women). Last reviewed . Educational information only — not medical advice.

What the "Fat-Burning Zone" Really Is

The fat-burning zone is the intensity band (roughly 60–70% HRmax, corresponding to Zone 2) where the highest percentage of your energy comes from fat oxidation. It is not the zone that burns the most fat calories in absolute terms — higher-intensity work burns more total calories, and a proportional share of those is still fat.

FATmax — The Individual Fat-Oxidation Peak

Sport scientists use the term FATmax to describe the exercise intensity at which an individual's fat oxidation is maximised. In lab studies using indirect calorimetry, FATmax falls between 55% and 72% of VO₂max for most adults, with trained endurance athletes able to sustain higher fat oxidation rates and at higher relative intensities than untrained subjects.

Reference: Achten J, Jeukendrup AE. Maximal fat oxidation during exercise in trained men. International Journal of Sports Medicine. 2003;24(8):603–8.

Fat Oxidation Rates: Trained vs Untrained

Group Peak fat oxidation Occurs at
Sedentary adult0.2–0.4 g/min~50% VO₂max
Recreationally trained0.4–0.6 g/min~60% VO₂max
Highly trained endurance0.7–1.0 g/min~65–72% VO₂max

Should You Actually Care About the Fat-Burning Zone?

If your goal is body composition, focus on weekly energy balance and total training volume — the zone breakdown matters less. If your goal is endurance performance (marathon, gran fondo, triathlon), improving fat oxidation is genuinely important: better fat metabolism spares glycogen and pushes back the point at which you "bonk." That is the real reason serious endurance athletes prioritise Zone 2.

Heart Rate Zones (reference: age 30, HRmax ≈ 187 bpm, Tanaka)

Zone Name % HRmax BPM (age 30) Primary use
1Recovery50–60%94–112Warm-up, recovery, active rest
2Endurance60–70%112–131Aerobic base, fat oxidation
3Aerobic70–80%131–150Tempo, aerobic capacity
4Hard80–90%150–168High-intensity, threshold-oriented work (not the same as measured LTHR)
5Maximum90–100%168–187Very-high-intensity, VO₂max-oriented intervals (reaching it does not prove VO₂max)

What Each Zone Feels Like (Talk Test)

Frequently Asked Questions

How accurate are heart rate calculators?

Formula-based calculators typically estimate HRmax within ±10–15 bpm. They are accurate enough to structure training for recreational athletes but not a substitute for a supervised max test.

What is the Karvonen method?

Karvonen uses heart rate reserve (HRR = HRmax − HRrest). Target HR = HRrest + (Intensity% × HRR). It personalises zones by accounting for resting heart rate.

Should I use different zones for cycling vs running?

Often, yes. Heart-rate zones can differ between running and cycling because physiological thresholds and heart-rate responses may vary by activity — many people see a lower heart rate on the bike at a similar effort, but the size of the difference is individual. Percentage-based zones are estimates, not measurements of your thresholds. For more precise training, establish your zones for the sport you perform, for example with a sport-specific test or the talk test.

Is Zone 2 the best zone for fat loss?

Zone 2 maximises the percentage of calories from fat, but higher intensities burn more total calories per minute. Long-term fat loss is driven by total weekly energy balance.

Disclaimer: This calculator is for informational purposes only and does not provide medical advice. Always consult with a healthcare professional before starting any new exercise program.