How this instrument works
This calculator applies the formula printed on more gym walls and cardio machines than any other: estimated maximum heart rate equals 220 minus your age in years. It traces to a 1971 review paper by Fox, Naughton and Haskell surveying cardiovascular research of the time, rather than a dedicated study built specifically to derive that one equation — the 220-minus-age line was drawn as a broad summary of the data the review covered, not fitted with the rigor of a purpose-built regression.
That origin shows up in the formula's accuracy: individual measured maximum heart rates commonly differ from the 220-minus-age estimate by 10 to 12 beats per minute or more, in either direction. For programming a single training session that spread rarely matters much, but for anything sensitive to a precise number, it's a meaningful margin to keep in mind rather than treat this figure as measured fact.
A more research-grounded alternative comes from Tanaka, Monahan and Seals, who in 2001 derived HRmax = 208 - (0.7 x age) from a meta-analysis spanning 492 groups and roughly 18,712 subjects. Their formula tends to track measured maximums more closely, particularly for older adults, where 220-minus-age is known to systematically underestimate. Trying both formulas side by side, or better yet getting an actual field or lab test, gives a fuller picture than either estimate alone.
- Enter Age in years — the only input this calculator needs.
- Read Estimated maximum heart rate — the 220-minus-age result, in beats per minute.
- Treat the number as a starting estimate for programming, not a measured ceiling — expect it to be off by roughly 10 bpm or more for many individuals.
- Feed the result into this site's heart-rate-zone, target-heart-rate or fat-burning-zone calculators if you need a training range or target built from it.
Worked example — a 30-year-old
Enter an age of 30. Estimated maximum heart rate is 220 - 30 = 190 bpm — the number this widely used convention predicts for someone of that age.
For comparison, plugging the same age into the alternative Tanaka, Monahan and Seals formula gives 208 - (0.7 x 30) = 187 bpm — close to this calculator's 190 bpm result at age 30, though the two formulas diverge more noticeably at older ages, where 220-minus-age tends to run lower than what's typically measured.
Questions
How accurate is the 220-minus-age formula?
Not very precise for any single individual, even though it's extremely widely used. Measured maximum heart rates commonly differ from the 220-minus-age estimate by roughly 10 to 12 beats per minute or more, in either direction — meaning the true number for a given 40-year-old could reasonably be anywhere from the high 160s to the low 190s despite the formula predicting exactly 180.
Is there a more accurate formula I should use instead?
Tanaka, Monahan and Seals proposed 208 - (0.7 x age) in 2001, derived from a meta-analysis of 492 subject groups totalling roughly 18,712 people — a much larger and more rigorously derived dataset than the 1971 review behind 220-minus-age. It tends to track measured values more closely, especially in older adults, where 220-minus-age is known to underestimate systematically. Neither formula replaces an actual measured maximum.
How do I get a truly accurate maximum heart rate?
The gold standard is a supervised, symptom-limited graded exercise test pushed to true exhaustion under medical supervision, which isn't practical or necessary for most casual training. A reasonable field alternative is the highest heart rate you record on a chest-strap monitor during a genuinely maximal effort, such as an all-out interval or a hard race finish.
Does fitness level change my maximum heart rate?
Not much, as a general rule — unlike resting heart rate, which reliably drops as cardiovascular fitness improves, maximum heart rate is largely determined by age and individual physiology rather than training status. Two people of the same age can have genuinely different maximums regardless of who's fitter, which is part of why any age-based formula is only ever an estimate.
What do I do with this estimate once I have it?
It's typically an input to another calculation rather than an endpoint on its own — this site's heart-rate-zone and target-heart-rate calculators use it (alongside resting heart rate) to build a training range or target, and the fat-burning-zone calculator applies a flat percentage directly to it. Plug in a measured maximum instead of this estimate in any of those if you have one.