Target Heart Rate Calculator

For most healthy adults the target heart rate is about 50–85% of maximum heart rate, with maximum estimated as 220 − age or the Tanaka equation, 208 − 0.7 × age — two formulas whose answers drift 0.3 bpm apart for every year of age away from 40, carrying every zone boundary with them.

Max heart rate calculator: where the number comes from

Training by heart rate starts with your maximum — the highest your heart can beat. The classic estimate is 220 − age. Tanaka and colleagues (2001), pooling more than 18,000 people, report that it understates the maximum in older adults, so this tool defaults to their equation (208 − 0.7 × age) and lets you switch. From your maximum it builds five training zones, each a fixed 10% band of it. This works as a max heart rate calculator on its own if that single number is all you came for; the zones below simply build on it.

If you add your resting heart rate, the calculator switches to the Karvonen (heart-rate-reserve) method, which subtracts your resting rate before applying each intensity and adds it back. Because it accounts for your fitness, Karvonen gives a more personal — and, at any intensity below 100%, always higher — target for the same zone. Measure resting HR first thing in the morning for the best figure; our guide to lowering resting heart rate covers how much it realistically moves.

Two formulas, and two sets of zones that do not line up

The dropdown above offers Tanaka and 220 − age as two menu items with nothing to choose between them. They are not interchangeable. The classic rule drops a full beat for every year of age; Tanaka drops 0.7. So the gap between them widens by 0.3 bpm per year of distance from age 40, where they meet. That is a modest difference in the headline number and a larger one once it is cut into five bands.

Take a 70-year-old. Tanaka returns a maximum of 159 bpm; 220 − age returns 150. Nine beats. But every zone is 10% of that maximum, so the whole ladder slides down with it. Tanaka's Zone 4 runs 127–143 bpm and the classic rule's runs 120–135. The bands are 16 and 15 beats wide and they share only eight beats. A reading of 140 bpm is Zone 4 — hard, sustainable threshold work — under Tanaka, and Zone 5 — short intervals only — under 220 − age. Same heart, same watch, different item selected in a dropdown.

Both ladders exactly as the calculator prints them at age 70, percentage-of-maximum method with the resting-HR box left blank. "Shared" is the overlap between the two bands carrying the same zone number; it narrows from 10 beats at the bottom of the ladder to 7 at the top, because each boundary moves by the 9-beat gap multiplied by that boundary's percentage — 5 beats at 60%, 7 at 80%, 9 at the top.

The mismatch is not confined to Zone 4. At 92 bpm the two ladders read Zone 1 and Zone 2; at 108, Zone 2 and Zone 3; at 124, Zone 3 and Zone 4; at 140, Zone 4 and Zone 5. At this age the disagreement only ever runs one way: wherever the two ladders differ, the classic rule reads the higher zone, never the lower, because its lower maximum makes the same pulse a larger share of it. Across the 7-to-10-beat overlap in each band — the "Shared" column above — they agree.

Below 40 the effect runs the other way, so there is no consistent bias you can mentally correct for. For a 20-year-old the classic rule gives the higher maximum — 200 against Tanaka's 194 — and therefore reads the same pulse as easier: 158 bpm is Zone 4 on Tanaka and Zone 3 on 220 − age. The sign flips in the late thirties. Once the calculator's rounding is applied, the two formulas return an identical maximum at ages 39, 40 and 41 — 181, 180 and 179 bpm — and differ by a single beat on either side of that.

How far apart Zone 4 sits, by age

Zone 4 is the 80–90% band, printed to whole beats by the percentage-of-maximum method. The bands themselves narrow with age — 20 beats wide at a maximum of 200, 15 at a maximum of 150 — because each is 10% of a maximum that falls. At 40 the two ladders are identical; at 70 they share 8 beats, half of the 16-beat Tanaka band.

So the rule is a short one: pick one formula and keep it. Nothing about you changes when you change the dropdown, so a zone that moves because you switched is not new information about your training. Past 40, the default here is Tanaka, whose source paper reports 220 − age understating the maximum in older adults. The two ladders are closest in the late thirties rather than simply below 40: at 30 the maximums are 187 and 190 and the Zone 4 bands, 150–168 and 152–171, share 16 beats, but by 20 the gap has reopened to 6 bpm — the same as at 60 — and the bands share 15.

None of this says which formula is right for you. Neither one measures you; both draw a line through a population, and individual maximums scatter around either line. That is an argument for holding your zones loosely, not for treating the two equations as the same thing. The narrower point stands on its own: the dropdown shifts your zones in a known direction by an amount you can compute, without learning anything new about you.

The resting-heart-rate box moves the zones further than the dropdown does

That field is optional and blank by default, so most people never touch it — and it is the input that changes the answer most. Leave it blank and each zone is a flat percentage of your maximum. Fill it in and the calculator switches to Karvonen, working on heart-rate reserve: your maximum minus your resting rate.

Stay with the 70-year-old on Tanaka, maximum 159. With the box blank, Zone 2 runs 95–111 bpm. Enter a resting rate of 60 and Zone 2 becomes 119–129 bpm. Those two bands do not overlap anywhere: 119 bpm, the floor of Karvonen's aerobic-base zone, sits inside Zone 3 under the percentage method. Same person, same formula, same zone number, two efforts that never meet.

The size of that jump is worth knowing, because it comes out of the two formulas cleanly. Karvonen gives (max − resting) × intensity + resting, and the percentage method gives max × intensity; subtract one from the other and the maximum cancels. The gap is your resting rate × (1 − intensity) — it does not depend on your age or your estimated maximum at all. At a resting rate of 60 that is 30 beats at Zone 1's floor, 24 at Zone 2's, 12 at Zone 4's, and nothing at all at the top of Zone 5, where both methods land on your maximum. The dropdown, by comparison, moves Zone 2's floor by 5 beats at age 70 and by less at every age closer to 40.

Karvonen also narrows every band, because each is 10% of reserve rather than 10% of maximum, and reserve is always the smaller number. At 159 max and 60 resting, reserve is 99, so each band is about 10 beats wide instead of about 16. Raise the resting rate to 80 and reserve falls to 79, making each band about 8 beats wide. Narrower bands make the formula choice matter more, not less: at 70 with a resting rate of 60, Tanaka's Karvonen Zone 4 is 139–149 bpm and the classic rule's is 132–141. They share two beats, against eight for the same pair by the percentage method.

There is a trap in the other direction too. With the box blank, Zone 1 begins at half your estimated maximum — 79.5 for our 70-year-old, printed as 80 bpm. For someone that age whose resting pulse is 80, that floor is their resting pulse: sitting still already registers as "recovery", because the percentage method has no way of knowing what their heart does at rest. Given that same 80, Karvonen puts Zone 1 at 120–127 bpm. If your resting rate sits at the upper end of the normal range, the blank box is not a neutral default.

What the formula cannot see

Both equations take exactly one input: age. Not sex, not training history, not medication. Beta blockers and similar rate-limiting drugs cap and lower heart rate, which throws off every age formula — zones for anyone taking them should come from a clinician, ideally from a supervised exercise test. There is also no field here for a measured maximum. If you have one from a lab test or a supervised maximal effort, it beats both equations, and you can put it to work in the heart-rate-ratio method of our VO₂ max calculator, which takes a measured maximum and resting rate directly.

That choice follows you across the site. The heart-rate-ratio method estimates VO₂ max as 15.3 × (maximum ÷ resting). For our 70-year-old with a resting rate of 60, feeding it Tanaka's 159 returns 40.5 ml/kg/min and 220 − age's 150 returns 38.3 — the two printed figures sit 2.2 ml/kg/min apart (2.30 before the calculator rounds each to one decimal), or 0.7 METs, produced entirely by the dropdown on this page.

Training in the right zone

Easy zones 1 and 2 build your aerobic base and should feel conversational; most endurance training lives here. Zone 3 sharpens aerobic fitness, zone 4 raises your lactate threshold, and zone 5 is peak effort for short intervals only. Individual maximums scatter around either line, so treat the numbers as a guide rather than a hard limit, and let how the effort actually feels overrule the band when the two disagree.

Use your zones to pace runs alongside the pace calculator, to set goal efforts with the race time predictor, and to structure easy days with the run-walk calculator. To see what a session in a given zone costs you in energy, pair it with the calories burned calculator. If you are new to exercise, older, pregnant, or managing a medical condition, check with a clinician before training hard.

The five training zones

The AHA suggests an overall 50–85% training range for most adults. The percentages are the same for both methods; Karvonen gives higher bpm because it adds your resting rate back, and narrower bands because reserve is smaller than maximum.

Max-HR: Tanaka et al. (2001) and the classic 220 − age; zones via Karvonen (heart-rate reserve); the VO₂ max figures use the heart-rate-ratio equation of Uth et al. (2004) as implemented in our VO₂ max calculator. All worked examples above are computed from those equations and this calculator's own fixed 10% zone bands, rounded to whole beats exactly as the tool prints them. Estimates only — not medical advice; check with a clinician before high-intensity training.