What are the five heart rate training zones?

Zone 1 (50-60% max): Recovery/warm-up. Zone 2 (60-70%): Fat burning/endurance base. Zone 3 (70-80%): Aerobic/cardiovascular fitness. Zone 4 (80-90%): Anaerobic/speed. Zone 5 (90-100%): Maximum effort/VO2 max.

Is the 220-minus-age formula accurate?

It provides a rough estimate with a standard deviation of 10-12 bpm. Your actual max HR may be higher or lower. For precise measurement, a graded exercise test supervised by a medical professional is recommended.

What is a good resting heart rate?

Normal adult resting HR is 60-100 bpm. Well-trained athletes may have resting rates of 40-60 bpm. Lower resting HR generally indicates better cardiovascular fitness. Consistently elevated resting HR may warrant medical evaluation.

Does resting heart rate change over time?

Yes. Regular cardiovascular exercise lowers resting HR over weeks and months. Illness, stress, dehydration, caffeine, and poor sleep can temporarily elevate it. Tracking resting HR trends reveals cardiovascular fitness progress.

Should I train in the fat-burning zone to lose weight?

Not necessarily. While a higher percentage of calories come from fat at lower intensities, higher-intensity exercise burns more total calories. For weight loss, total calorie expenditure matters more than the fuel source. A mix of intensities is most effective.

Heart Rate Calculator

Find your maximum heart rate and target training zones based on age and resting heart rate.

Heart Rate Calculator

Calculate your target heart rate zones

Target Heart Rate

Based on age-predicted max heart rate

Age

Formula

Max HR = 220 - age

What Is Maximum Heart Rate?

Your maximum heart rate (Max HR) is the highest number of beats per minute your heart can sustain during intense physical exertion. It is a fundamental benchmark in exercise science — it tells you the absolute ceiling of your cardiovascular effort. Max HR naturally declines with age and is largely determined by genetics, not fitness level. Knowing your Max HR allows you to train with precision rather than guesswork.

Target heart rate zones are percentage ranges of your Max HR used to guide exercise intensity. Each zone produces different physiological effects: the fat-burning zone (60–70%) burns a higher proportion of calories from fat; the aerobic or cardio zone (70–80%) builds cardiovascular endurance; the threshold zone (80–90%) increases lactate tolerance and speed; and the peak or VO2 max zone (90–100%) pushes your upper limits for short bursts. Training across all zones produces a well-rounded fitness base.

How to Use This Calculator

1Enter your age in years — this is the primary input for both the Fox and Tanaka formulas.
2Optionally enter your resting heart rate (measured in the morning before getting up) to enable the Karvonen method for a more personalized result.
3Click Calculate to instantly see your maximum heart rate and all five training zones.
4Use the displayed BPM ranges to guide your workouts — wear a heart rate monitor and aim to stay within your target zone.

Formulas Used

Maximum Heart Rate:
  Fox Formula:     Max HR = 220 − age
  Tanaka Formula:  Max HR = 208 − (0.7 × age)  [more accurate for older adults]

Target Heart Rate Zones (% of Max HR):
  Zone 1 — Warm-up:        50–60%
  Zone 2 — Fat Burn:       60–70%
  Zone 3 — Aerobic/Cardio: 70–80%
  Zone 4 — Threshold:      80–90%
  Zone 5 — Peak/VO2 Max:   90–100%

Karvonen Method (uses resting HR):
  Target HR = ((Max HR − Resting HR) × Intensity%) + Resting HR

The Tanaka formula (208 − 0.7 × age) is recommended for adults 40 and older as it corrects for the over-estimation in the classic Fox formula. The Karvonen method produces a more personalized target range by incorporating your resting heart rate — also called heart rate reserve — into the calculation.

Worked Examples

Age 30 — Fox Formula

Max HR = 220 − 30 = 190 bpm. Fat-burn zone (60–70%) = 114–133 bpm. Cardio zone (70–80%) = 133–152 bpm. For a 30-minute moderate run, targeting 133–152 bpm keeps you solidly in the aerobic zone, improving endurance and cardiovascular health.

Age 50 — Tanaka Formula

Max HR = 208 − (0.7 × 50) = 208 − 35 = 173 bpm. Threshold zone (80–90%) = 138–156 bpm. Because the Tanaka formula accounts for the slower age-related HR decline in fit older adults, this is a more reliable target for a 50-year-old athlete training for a half-marathon.

Age 40, Resting HR 65 — Karvonen Method

Max HR (Fox) = 220 − 40 = 180 bpm. Heart rate reserve = 180 − 65 = 115 bpm. Target HR at 70% intensity = (115 × 0.70) + 65 = 80.5 + 65 = 145.5 bpm. The Karvonen result of ~146 bpm is noticeably higher than a plain 70% of Max HR (126 bpm), reflecting the fact that a lower resting heart rate signals better cardiovascular conditioning.

Frequently Asked Questions

What is a normal resting heart rate?▾

For most healthy adults, a normal resting heart rate falls between 60 and 100 beats per minute. Well-trained athletes often have resting heart rates in the 40–60 bpm range. A consistently high resting heart rate (above 100 bpm) is called tachycardia and may warrant a check-up with your doctor.

Is the 220 − age formula accurate?▾

The Fox formula (220 − age) is a widely used estimate, but it carries a standard deviation of about ±10–12 bpm, meaning your actual Max HR could differ significantly from the prediction. The Tanaka formula tends to be more accurate for adults over 40. The only truly precise way to measure Max HR is via a supervised maximal exercise stress test.

What zone burns the most fat?▾

The fat-burning zone (Zone 2, 60–70% Max HR) burns the highest percentage of calories from fat, but at a lower absolute rate. Higher-intensity zones burn more total calories per minute, which can lead to greater overall fat loss. A mix of moderate and high-intensity training is generally most effective for body composition.

How do I measure my heart rate during exercise?▾

The most convenient options are a chest strap heart rate monitor (most accurate), a GPS sports watch with optical HR sensor, or a fitness tracker on your wrist. You can also take a manual pulse at your wrist (radial artery) or neck (carotid artery): count beats for 15 seconds and multiply by 4.

What is heart rate variability (HRV)?▾

Heart rate variability (HRV) is the variation in time between consecutive heartbeats. Despite sounding like an irregular heartbeat, higher HRV is associated with better cardiovascular fitness, lower stress, and faster recovery. Many sports watches and fitness apps now track HRV to help athletes monitor readiness and avoid overtraining.