Heart rate & training zone calculator
Calculate your maximum heart rate and your five training zones in beats per minute. Train in the right zone for your goal —endurance, fat-burn or speed— instead of always going at the same intensity. Add your resting HR and we use the more accurate Karvonen method.
Your beats per minute at rest, on waking. If you enter it, we use the Karvonen method (more accurate).
Your estimated maximum heart rate
190
bpm
Your training zones
Method: % of your max HR
Very easy. Warm-up and active recovery.
Comfortable, you can talk. Endurance base and fat use.
Moderate-high. Improves aerobic capacity.
Hard, heavy breathing. Raises your threshold and speed.
All-out effort. Short bouts only (intervals).
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Rough estimate (220 - age formula). Not a substitute for a stress test or medical advice.
How are heart rate zones calculated?
First we estimate maximum heart rate (HRmax) with the classic 220-minus-your-age formula; a useful approximation for most, though everyone varies. On that HRmax we define five zones by intensity percentage: Z1 recovery (50-60%), Z2 easy aerobic or "fat-burn" (60-70%), Z3 aerobic (70-80%), Z4 threshold (80-90%) and Z5 maximum (90-100%). If you know your resting heart rate, the Karvonen method —which uses the "reserve" (HRmax minus resting HR)— fits the zones better to your fitness. Zone 2 is the base: comfortable, you can talk, and where most endurance is built. To truly improve, combine lots of low-zone volume with some hard work in Z4-Z5.
FAQ
What is my maximum heart rate?
The most-used estimate is 220 minus your age: e.g. at 30 it is around 190 bpm. It is a population average; your real max may be a bit higher or lower. Alternatives like Tanaka (208 minus 0.7 x age) refine it in older people. The only exact way to know it is a stress test.
What is the fat-burning zone?
It usually sits in Z2 (60-70% of HRmax): a comfortable pace where the body uses a higher percentage of fat as fuel. Watch the myth: although the PERCENTAGE of fat burned is higher in Z2, to LOSE fat what rules is total calories and the deficit; training harder burns more total calories. Z2 is great for another reason: it is sustainable, builds aerobic base and barely fatigues.
What is the Karvonen method?
It is a more precise way to calculate zones that accounts for your resting heart rate, not just the maximum. It uses "heart-rate reserve" (HRmax minus resting HR) and applies the percentage to it. Since your resting HR reflects your fitness, Karvonen zones fit you better. So if you know your resting bpm, this calculator uses them automatically.
Which zone should I train in?
It depends on the goal, but the rule that works for most is "80/20": most of the time (about 4 of every 5 days) in low, comfortable zones (Z1-Z2), where endurance builds without piling on fatigue, and a small part in high zones (Z4-Z5) for speed and threshold. Always going at medium intensity (Z3) is the classic mistake: very tiring, little improvement. Alternate truly easy with truly hard.
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