See your five training zones two ways: percentages of your estimated maximum heart rate and Karvonen reserve targets from your resting rate.
All calculations happen entirely in your browser. Your age and resting heart rate are never transmitted to any server.
Measure it first thing in the morning, lying in bed before you get up.
No sex selection is needed: the maximum-heart-rate formulas used here are genderless population averages.
This calculator estimates your maximum heart rate with two published formulas, then lays five training zones on top of it twice: once as simple percentages of that maximum, and once with the Karvonen method, which folds your resting heart rate into every band.
Traditional: HRmax = 220 − ageTanaka: HRmax = 208 − 0.7 × ageTarget = HRrest + pct × (HRmax − HRrest) The difference between your maximum and your resting rate — the heart-rate reserve — is the range you can actually rev your heart through. Karvonen applies the percentage to that reserve instead of the raw maximum, so a lower resting rate shifts the whole table upward: two people of the same age with different fitness get different zones from the same formulas.Not very, for any single person. The rule traces back to a 1970s observation, and measured maximums scatter around it with a population variance of roughly ±10–12 beats per minute. The Tanaka equation (208 − 0.7 × age) used in this table is a 2001 meta-analytic refit across hundreds of maximal tests — less biased on average, but still an estimate. Only a supervised all-out test finds your true maximum.
No, not as numbers on a screen. Beta-blockers and some other heart-rate-active medications blunt the heart's response, so your true maximum is lower than any age formula says and the calculated zones will be too high to reach. Use perceived exertion and the talk test instead, and talk to your prescribing doctor before training to heart-rate targets.
For zone work, a chest strap. Wrist optical sensors are good for all-day averages but lag several seconds behind rapid heart-rate changes and pick up motion artifact during intervals, so short zone-4/5 reps can read low. The strap's ECG signal is the reference the zone formulas were built against.
It is the second band here (60–70% of max): an intensity where you can still hold a conversation in full sentences. Recreational endurance training often spends most of its volume there because it is sustainable and builds an aerobic base with low fatigue. That is a general training convention, not a medical claim — what matters for health is moving regularly at a level you enjoy.
No. The whole calculator is a few lines of vanilla JavaScript running in your browser. Your age, resting heart rate and results never leave your device — there is no account, no tracking and no network request attached to a calculation.
If you just finished with Heart Rate Zone Calculator, the natural next steps are Running Pace Calculator, Steps Calculator, One Rep Max Calculator, or browse every tool in Health Tools.