Target Heart Rate Calculator
Find your personal exercise heart rate zones using the Karvonen formula — from fat burn to peak performance.
About this tool
Calculate your personal target heart rate zones for different exercise intensities using the scientifically-validated Karvonen (heart rate reserve) formula. Enter your age and resting heart rate to see your fat burn, aerobic, threshold, VO2 max, and peak zones with bpm ranges and training guidance.
How to use it
Quick steps to get the most out of this utility.
- 1
Enter your age
Type your age in years. Your max heart rate is calculated automatically using the Tanaka formula.
- 2
Optionally add resting heart rate
For more accurate zones, enter your resting heart rate (ideally measured first thing in the morning). Default is 70 bpm.
- 3
Review your zones
See your 5 target heart rate zones with bpm ranges and training guidance for each intensity level.
Understanding Heart Rate Zones
Heart rate zone training is a proven method for structuring exercise intensity. By training in different zones, you can target specific physiological adaptations — from fat burning and aerobic endurance to anaerobic power and VO2 max.
This calculator uses the Karvonen formula (also called the heart rate reserve method), which is more personalised than simple percentage-of-max approaches because it accounts for your resting heart rate. The formula: Target HR = (Heart Rate Reserve × %intensity) + Resting HR.
The Tanaka formula (208 − 0.7 × age) is used for max heart rate, as research shows it is more accurate than the traditional 220 − age formula, especially for adults over 30.
Frequently asked questions
How is max heart rate calculated?+
This calculator uses the Tanaka formula: 208 − (0.7 × age). Research shows this is more accurate than the traditional 220 − age formula, especially for people over 30.
What is the Karvonen formula?+
The Karvonen formula (heart rate reserve method) calculates target heart rate zones by accounting for your resting heart rate: Target HR = (Heart Rate Reserve × %intensity) + Resting HR. Heart Rate Reserve = Max HR − Resting HR.
What is a normal resting heart rate?+
For adults, a normal resting heart rate is 60–100 bpm. Well-trained athletes often have lower resting heart rates (40–60 bpm) due to better cardiovascular fitness. Measuring resting HR first thing in the morning gives the most accurate reading.
Which zone should I train in?+
Most adults benefit from spending most of their exercise time in the Light to Moderate zones (50–70% intensity) for building aerobic base. Higher intensity zones (Hard, Maximum, All-Out) should be used sparingly and progressively.
Are heart rate zones the same for everyone?+
No. Heart rate zones are individualised based on your age and resting heart rate using the Karvonen formula. They can also be affected by medications (especially beta-blockers), fitness level, altitude, and health conditions.
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