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Target Heart Rate Calculator
Find your maximum heart rate and the five training zones — by age, or with the Karvonen method using your resting heart rate.
Training at the right intensity makes exercise both safer and more effective. Your heart rate is an easy, objective guide: easy endurance work happens in the lower zones, while intervals and races push into the upper ones. This calculator works out your estimated maximum heart rate from your age and divides it into five training zones in beats per minute.
If you enter your resting heart rate, the zones are calculated with the Karvonen method, which accounts for your fitness and is usually more accurate. If you have measured your maximum in a fitness test, enter that instead of the age estimate. You also see the moderate and vigorous ranges used in public health guidelines. Nothing you enter is stored or sent.
How to use Target Heart Rate Calculator
- Enter your age.
- Optionally enter your resting heart rate and a measured maximum.
- Choose the formula for maximum heart rate.
- Read your maximum heart rate and the zones in beats per minute.
Features
- Maximum heart rate: Tanaka (208 − 0.7 × age) or 220 − age.
- Five training zones in beats per minute.
- Karvonen heart-rate-reserve method with your resting rate.
- Use a measured maximum if you have one.
- Moderate and vigorous intensity ranges.
- Runs in your browser; nothing is stored or sent.
Maximum heart rate
The classic formula 220 − age is easy to remember but was never based on careful research, and it underestimates the maximum for older adults. The Tanaka formula, 208 − 0.7 × age, comes from an analysis of hundreds of studies and is generally more accurate, so it is the default here. Both are averages: individual maximums vary by 10 beats or more either way at the same age. A supervised exercise test, or the highest rate you reliably see in all-out efforts, gives your real maximum — enter it if you know it.
The five zones
Zones are given as a percentage of maximum heart rate, or, with the Karvonen method, of heart-rate reserve — the difference between your maximum and resting rates. Karvonen adds your resting rate back on, so fitter people with a lower resting rate get zones that better match their effort.
| Zone | Intensity | What it trains |
|---|---|---|
| 1. Very light | 50–60% | Recovery, warm-up, cool-down |
| 2. Light | 60–70% | Endurance base, fat burning |
| 3. Moderate | 70–80% | Aerobic fitness |
| 4. Hard | 80–90% | Lactate threshold, speed endurance |
| 5. Maximum | 90–100% | Short sprints and intervals |
Moderate and vigorous exercise
Health guidelines recommend at least 150 minutes of moderate activity, or 75 minutes of vigorous activity, each week. The American Heart Association describes moderate intensity as about 50–70% of maximum heart rate and vigorous intensity as about 70–85%. A simple check: during moderate exercise you can talk but not sing; during vigorous exercise you can only say a few words before needing a breath. Spending most training time in the lower zones and a smaller part in the higher ones is a pattern that works well for most people.
Measuring your heart rate
Measure your resting heart rate in the morning, after waking and before getting up: count your pulse at the wrist or neck for a full minute, and average a few days. During exercise, a chest strap gives the most accurate reading; wrist-based trackers can lag behind or be thrown off by movement. Medicines such as beta blockers lower heart rate and make age-based zones meaningless, and people with heart conditions should get personal limits from their doctor or a cardiac rehabilitation team.
Frequently asked questions
How do I calculate my maximum heart rate?
A common estimate is 208 − 0.7 × age (Tanaka). The older formula is 220 − age.
What is the fat-burning zone?
Zone 2, about 60–70% of maximum, where the body uses a higher share of fat for fuel. Total calories still matter most for weight loss.
What is the Karvonen formula?
Target = resting rate + intensity × (maximum − resting). It accounts for your fitness.
What is a good resting heart rate?
60–100 bpm is normal for adults; fit people often have lower rates.
Do medicines affect the zones?
Yes. Beta blockers and some other medicines lower heart rate, so ask your doctor for your limits.
Why are my zones different from my fitness watch?
Watches may use another formula, a measured maximum or your heart-rate reserve. Enter the same inputs here to compare.
Is my data stored?
No. Everything is calculated in your browser.
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