No max-HR test? Estimate it from age.
Type your age and pick a formula. We estimate your max heart rate and split it into 5 training zones — for runners, cyclists and triathletes who don’t want to redline a 3-min hill rep just to set training zones.
Tanaka et al. (2001) ran a meta-analysis of 351 studies and 18,712 subjects and found 208 − 0.7 × age fit the data better than the famous 220 − age, with a standard deviation around 7 bpm. Fox/Haskell (220 − age) is what most chest straps default to — convenient but with variance up to ±15 bpm in individuals. Gulati et al. (2010) tracked 5,437 healthy women and found 206 − 0.88 × age matched the female population significantly better than the male-derived formulas. Pick Tanaka unless you have a specific reason; pick Gulati for women if you want a formula calibrated to female data.
These zones get you 80% of the way there with zero risk. If you’re running structured threshold work or VO₂max intervals where 5-bpm precision matters, do a field test or a lab VO₂max protocol — your individual max-HR can sit ±10-15 bpm from any age formula. Add a resting-HR measurement to switch this calculator into Karvonen %HRR mode, which corrects for low or high resting rates.
The formulas and ranges above are grounded in the following peer-reviewed literature.
Default formula in our calculator. Meta-analysis of 351 studies (n=18,712) — better fit than 220-age (RMSE ~7 BPM vs ~12).
Read paperMost recent large-sample validation (n=3,320 healthy Norwegian adults). Performs slightly better than Tanaka in physically active populations.
Read paperValidated specifically for women (n=5,437). Predicts ~5-7 BPM lower than gender-neutral formulas — used here as the female-specific option.
Read paperOrigin of the famous 220-age formula. Included for completeness — newer formulas above are more accurate, but 220-age remains widely cited.
View on PubMedOrigin of the heart-rate-reserve (HRR) method. We use it when you provide a resting HR — better than %maxHR alone because it accounts for individual fitness.
View on PubMedUse our precise heart rate zones calculator — it takes your tested max HR plus resting HR and computes Karvonen %HRR zones. That tool is the gold standard once you’ve done a field test or lab protocol; this estimator is the no-test starting point.
They were derived from different populations. Tanaka (2001) is the best general estimate from a meta-analysis of mostly mixed-gender adult data. Fox/Haskell (220 − age) is the 1971 textbook formula — popular but less accurate. Gulati (2010) is calibrated specifically to a 5,437-woman cohort and predicts female max HR better than male-derived formulas.
Standard deviation is around ±7 bpm for Tanaka and Gulati, ±10-15 bpm for Fox/Haskell. Useful enough for easy/aerobic zones; risky if you’re training right at threshold and need 5-bpm precision. If you suspect your real max HR is far from age-predicted (which is common), do a field test.
Yes if you know it. Adding resting HR switches us from %max-HR zones to Karvonen %HRR zones — heart rate reserve = max − resting. Karvonen accounts for the gap between your resting HR and your max, which makes the zones much more accurate, especially for athletes with resting rates well below 60 or above 75 bpm.
Cycling max HR runs 5-10 bpm lower than running for most people; swimming runs 10-15 bpm lower (the prone position triggers the diving reflex). Either re-test per sport or shave 7-10 bpm off the running max for cycling and 12 bpm for swimming.
Heat raises HR by 5-10 bpm at any given effort — known as cardiac drift. On hot or humid days, a Z2 effort can push you into Z3 territory by HR alone. Cap effort by perceived exertion or pace, not heart rate, when conditions are bad.