Target Heart Rate Zone Calculator

Training by heart rate takes the guesswork out of exercise, and the key is knowing your personal zones rather than a one-size-fits-all number. This calculator works out your five target heart rate training zones in beats per minute using the Karvonen method, the approach favoured by coaches because it accounts for your resting heart rate, not just your age. The idea is simple but powerful: a fitter person with a low resting pulse has a wider heart rate reserve to work within, so their zones land in different places from someone of the same age who is just starting out. You enter your age, which sets your estimated maximum heart rate, and your resting heart rate, ideally measured first thing in the morning before you get out of bed. The calculator finds your heart rate reserve, the gap between your maximum and resting rates, and lays out the beats-per-minute range for each of the five zones from very light recovery through to maximum effort. Each zone has a job: the easy aerobic and fat-burning zones build endurance and let you train often without burning out, the cardio zone lifts your fitness, and the hard threshold and peak zones sharpen speed and power in short doses. Most people get the best results doing the bulk of their training easy and only a little at the top end, and seeing the actual numbers makes that far easier to stick to on a watch or chest strap. Whether you run, ride, row or walk, these zones give every session a clear target. The figures are estimates, and you should check with a doctor before starting vigorous exercise.

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yrs
bpm
Estimated max HR190bpm
Heart rate reserve130bpm
ZoneIntensityTarget (bpm)

Maximum heart rate estimated as 220 minus age. Zones use the Karvonen heart rate reserve method. Estimates only, not medical advice. Check with a doctor before starting vigorous exercise.

How it works

The calculator estimates your maximum heart rate as 220 minus your age, then subtracts your resting heart rate to find your heart rate reserve. For each zone it takes the intensity percentage of that reserve and adds your resting heart rate back on. This Karvonen formula, target equals reserve times intensity plus resting rate, personalises the zones to your fitness rather than using a flat percentage of maximum.

Worked example

At age 30 your estimated maximum is 190 bpm. With a resting rate of 60, your reserve is 130 bpm. The cardio zone at 70 to 80 percent runs from 0.70 times 130 plus 60, which is 151 bpm, up to 0.80 times 130 plus 60, which is 164 bpm. So a steady cardio session for this person sits at roughly 151 to 164 beats per minute.

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