Tanaka formula: 208 − 0.7 × age
Maximum Heart Rate
187bpm
Scenario
Target Heart Rate for Weight Loss — Burn More Fat
Find your optimal fat-burn heart rate zone using the target heart rate calculator, with Zone 2 training guidance, calorie deficit strategies, and realistic weight loss expectations.
Interactive Calculator
Your Details
years
bpm
Your estimated max heart rate: 187 bpm
Using Tanaka formula: 208 − (0.7 × 30)
Using Tanaka formula: 208 − (0.7 × 30)
Your Heart Rate Zones
Training Zones (Karvonen HRR Method)
Zone 1 — Very Light
Zone 2 — Light
Zone 3 — Moderate
Zone 4 — Hard
Zone 5 — Maximum
The formula
The formula
How Heart Rate Zones Are Calculated
Your heart rate training zones are calculated using the Karvonen Heart Rate Reserve (HRR) method, which considers both your maximum heart rate and resting heart rate for a personalized result. This is more accurate than using an age-based formula alone, because it takes your baseline fitness (reflected by resting heart rate) into account. A fit person with a low resting heart rate will have zones that start lower than someone with a higher resting heart rate.
Maximum heart rate is estimated using the Tanaka formula, which is considered more accurate than the traditional 220 − age formula across a broader range of ages. The combination of Tanaka for maximum heart rate and the Karvonen method for the reserve produces five distinct training zones, each targeting a specific physiological adaptation.
The Formula
Max HR = 208 − (0.7 × Age)
HR Reserve = Max HR − Resting HR
Zone HR = Resting HR + (HRR × Zone %)
Tanaka formula (2001) — more accurate than the traditional 220 − age formula
Formula Source
This calculator uses the **Karvonen heart rate reserve method** for zone calculation and the **Tanaka formula for maximum heart rate** from **Tanaka H, Monahan KD, Seals DR, Journal of the American College of Cardiology** published in **2001**.
Reference URL: https://pubmed.ncbi.nlm.nih.gov/11153730/
Last Verified: 2026-07-30
Five Heart Rate Zones
| Zone | % of HRR | Perceived Effort | Training Benefit |
|---|---|---|---|
| Zone 1 | 50–60% | Very Light | Recovery, warm-up |
| Zone 2 | 60–70% | Light | Fat burning, aerobic base |
| Zone 3 | 70–80% | Moderate | Aerobic endurance |
| Zone 4 | 80–90% | Hard | Lactate threshold |
| Zone 5 | 90–100% | Maximum | VO2 max, speed |
Worked Example
Consider a 35-year-old with a resting heart rate of 60 bpm. Max HR = 208 − (0.7 × 35) = 183.5 bpm. HR Reserve = 183.5 − 60 = 123.5 bpm. For Zone 2 (60–70% of HRR): lower bound = 60 + (123.5 × 0.60) = 134 bpm, upper bound = 60 + (123.5 × 0.70) = 146 bpm. So your Zone 2 target range is approximately 134–146 bpm. A heavier or less fit person with a resting heart rate of 80 bpm would have a correspondingly lower Zone 2 range.
FAQ-Style Explanations
Why is the Karvonen method better than the percentage of max HR method? The reserve method accounts for your resting heart rate, which reflects your fitness level. Two people of the same age can have very different training zones if one is a trained athlete with a resting heart rate of 45 and the other is sedentary with a resting heart rate of 80.
Can I use the 220 − age formula instead? Yes, it is still widely used because it is simple. However, the Tanaka formula (208 − 0.7 × age) predicts maximum heart rate more accurately, especially for older adults, where the classic formula tends to underestimate.
Do zone numbers change as I get fitter? Yes. As your resting heart rate drops with improved fitness, your HR reserve increases and your zones shift. Recalculate your zones every 3–6 months, especially after periods of consistent training.
Known Limitations
- Maximum heart rate formulas are population estimates. The only way to know your true max is a maximal exercise test, which should be done under medical supervision.
- Heart rate is influenced by stress, caffeine, sleep, hydration, and heat, which can shift your working zones on any given day.
- Some medications (beta-blockers, etc.) blunt heart rate response, making formula-based zones unreliable. If you take such medications, work with a provider to set appropriate zones.
Scenario guide
Scenario guide
The Fat-Burn Zone: 50-60% of Max Heart Rate
The fat-burn zone is defined as 50-60% of your maximum heart rate. For a 40-year-old with a max HR of 180 bpm (using the Fox formula: 220 - 40), this zone spans 90-108 bpm. Exercise in this range uses a higher percentage of fat as fuel — approximately 60-70% of total energy — compared to 30-40% fat utilization at higher intensities. Use the HealthCalc Target Heart Rate Calculator to input your age and find your exact fat-burn zone boundaries. This zone is also where conversation remains comfortable (the "talk test"), making it an accessible starting point for beginners building cardiovascular fitness.
Total Calories vs Fat Percentage: What Really Matters
While the fat-burn zone uses a higher percentage of fat, higher-intensity exercise burns more total calories and can therefore burn more absolute fat per session. A 30-minute run at 80% max HR (Zone 4) might burn 400 total calories with 40% from fat (160 fat calories), while a 60-minute walk at 60% max HR might burn 300 total calories with 65% from fat (195 fat calories). The 60-minute lower-intensity session burns slightly more fat calories, but the time investment doubles. For weight loss, total calorie deficit over the week matters most — not the specific percentage of fat used during any single workout. Choose an intensity that allows you to exercise consistently and for longer durations.
Zone 2 Training for Fat Adaptation
- Endurance base building: Spend 70-80% of weekly training time in Zone 2 (60-70% max HR). This builds mitochondrial density and capillary networks that improve your body's ability to use fat as fuel at all intensities.
- Fat adaptation timeline: Consistent Zone 2 training over 6-8 weeks significantly improves fat oxidation rates. Athletes who follow a high-Zone-2, low-intensity training model can burn 50-60% more fat per minute at a given intensity after adaptation.
- Recovery benefit: Zone 2 sessions promote blood flow and nutrient delivery without triggering the high cortisol and inflammation of hard sessions, speeding recovery between harder workouts.
- Sustainability: Because Zone 2 feels comfortable and does not feel like "work," most people can sustain 45-90 minutes per session 3-5 times per week, creating a meaningful weekly calorie expenditure without burnout.
Combining Cardio with a Calorie Deficit
Effective weight loss requires a sustained calorie deficit of 500-1000 kcal per day, producing 0.5-1 kg of fat loss per week. Cardio in the fat-burn zone adds 200-500 kcal of daily expenditure depending on intensity and duration, and should complement — not replace — dietary changes. Use the HealthCalc TDEE Calculator to determine your total daily energy expenditure, then subtract 500-750 kcal for your target intake. Combine 3-4 Zone 2 cardio sessions per week (45-60 minutes each) with 2 strength training sessions to preserve lean muscle during the deficit. Expect realistic results of 0.5-1 kg per week; faster loss typically indicates water or muscle loss rather than pure fat loss.
FAQ
Frequently Asked Questions
The fat-burn zone is 50-60% of your max heart rate (Zone 1). For a 40-year-old with max HR 180, that means 90-108 bpm. This zone maximizes fat as a percentage of fuel, though total calorie deficit over the week matters most for weight loss.
Yes, but primarily because it allows longer, more sustainable sessions. Higher intensities burn more total calories per minute and can be equally or more effective for fat loss if you can sustain them.
Zone 2 is 60-70% of max heart rate. It builds aerobic endurance, increases fat-oxidation capacity, and is sustainable for 45-90 minutes per session. Most coaches recommend 70-80% of weekly training volume in Zone 2.
A 70 kg person in Zone 2 (light-moderate jogging or brisk walking) burns approximately 250-400 kcal per hour, depending on exact intensity and body weight.
Absolutely. Weight loss is driven by total calorie deficit. High-intensity intervals, strength training, or any form of consistent physical activity combined with a caloric deficit will produce fat loss regardless of the specific heart rate zone.
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