Health⏱ 5 min read
How Accurate Is the 220 Minus Age Formula for Max Heart Rate?
The 220-age formula is widely used but systematically inaccurate for many people. Here are six alternative formulas, what determines true max HR, and how to measure it directly.
The 220-age formula has been in use since 1971 and is the default in every piece of gym equipment. It was never intended as a precise formula -- it was a rough observation from a handful of studies. More accurate alternatives exist.
The 220-Age Formula and Its Error
220 - age (the classic formula)
Standard deviation: approximately +/- 12 beats per minute
This means for a 40-year-old (predicted MHR = 180):
68% of people: 168-192 bpm (within 1 SD)
95% of people: 156-204 bpm (within 2 SD)
A 40-year-old could have a true MHR anywhere from 155-205 bpm
and still be entirely normal.
The formula is systematically inaccurate:
- Overestimates MHR for fit older adults
- Underestimates MHR for unfit younger people
- Poorly calibrated for people outside the original study population
More Accurate Alternative Formulas
Tanaka formula (2001, 514 subjects, widely validated):
MHR = 208 - (0.7 x age)
40-year-old: 208 - 28 = 180 (same here, but different slope)
60-year-old: 208 - 42 = 166 (vs 160 from 220-age)
20-year-old: 208 - 14 = 194 (vs 200 from 220-age)
Gellish formula (2007, 3,320 subjects):
MHR = 206.9 - (0.67 x age)
40-year-old: 206.9 - 26.8 = 180.1
60-year-old: 206.9 - 40.2 = 166.7
20-year-old: 206.9 - 13.4 = 193.5
Both give similar results to 220-age for middle-aged adults
but diverge more at the extremes (very young, very old).
Gender and Fitness Adjustments
Women's MHR (Nes formula, 2013):
MHR = 211 - (0.64 x age)
Women aged 40: 211 - 25.6 = 185.4 (vs 180 for men)
Research suggests women's max HR is on average 5-8 bpm higher
than men's at the same age, though formulas often ignore this.
Highly trained athletes:
Often show 5-10 bpm lower MHR than age-predicted
Due to cardiac adaptation and slower intrinsic rate
Sedentary individuals:
Often show 5-10 bpm higher MHR than age-predicted
Training affects resting HR more than max HR
Directly Measuring Your Max Heart Rate
Most accurate: laboratory VO2 max test
Practical alternatives:
Running test:
Warm up 10-15 minutes at easy pace
Run at 85% effort for 3 minutes
Increase to 90% effort for 2 minutes
Sprint maximally for final 60-90 seconds
Highest HR recorded = estimated MHR
Cycling hill repeat test:
3 x 3-minute hill repeats with full recovery
Maximum HR at end of third repeat = estimated MHR
Note: you must be fit before attempting these tests.
Not recommended without medical clearance if previously sedentary,
over 45, or with any cardiovascular risk factors.