About the Life Expectancy Calculator
This life expectancy calculator estimates how many more years you can expect to live, on average, given your current age and sex, and how common lifestyle factors — smoking, physical activity, body weight and alcohol — shift that estimate. It also shows your chance of reaching 80, 90 and 100 and a survival curve compared with the average person of your sex.
The baseline comes from a mortality model fitted to the final 2024 US figures published by the CDC’s National Center for Health Statistics in January 2026: life expectancy at birth of 76.5 years for men and 81.4 for women, and 18.4 and 20.8 further years at age 65. Because you have already survived to your current age, your expected age at death is higher than the life expectancy at birth figure that makes headlines — a 65-year-old man, for example, can expect to live to about 83.4.
Lifestyle factors are applied as rounded, approximate relative risks (multipliers on the whole mortality curve) loosely based on large cohort studies, and are assumed to be independent of one another. This is an educational estimate for populations, not a personal prediction: family history, medical conditions, income, where you live and plain chance all matter, and life expectancy has been changing year to year. Use it to see which habits make the biggest difference.
With the default inputs, the estimated years remaining is 40.7 years. Change any value above to recalculate instantly.
How to use the life expectancy calculator
- 1Enter your current age and sex.
- 2Choose your smoking status and typical activity level.
- 3Select your BMI range and weekly alcohol intake.
- 4Read your estimated remaining years and age at death.
- 5Change one answer at a time to see which habit has the biggest effect.
Formula and method
Mortality is modelled with the Gompertz-Makeham law: a small constant background risk C plus a risk that roughly doubles every 7–9 years of age. The constants for men and women are fitted so the model reproduces the final 2024 CDC/NCHS figures for US life expectancy at birth (76.5 men, 81.4 women) and at 65 (18.4 and 20.8 years). Remaining life expectancy is the area under your survival curve from your current age onward, computed numerically in 0.1-year steps.
Lifestyle answers multiply the whole mortality curve by a factor m (for example about 2.0 for current smoking versus 0.85 for never smoking, reflecting the roughly 2–3× death rates reported for smokers). These factors are rounded, simplified from large cohort studies and assumed to be independent, so treat the result as an illustration of relative effects rather than a forecast.
- μ(x)
- Annual mortality rate (hazard) at age x
- m
- Combined lifestyle risk multiplier (1.0 = average)
- S(x→y)
- Probability of surviving from age x to age y
Worked examples
40-year-old man, never smoked, some activity, overweight
The average 40-year-old man in the model can expect to live to about 78.8. Never smoking lowers mortality to 0.85× average, which adds roughly 1.9 years, for an estimated lifespan of about 80.7.
65-year-old woman, healthy BMI, active, never smoked
An average 65-year-old woman can expect about 20.8 more years (CDC, 2024). Her combined multiplier is 0.85 × 0.9 × 0.95 ≈ 0.73, which extends that to around 23.5 years and gives her roughly a 47% chance of reaching 90.
50-year-old male smoker, inactive, BMI 30–34.9
Smoking (2.0×), inactivity (1.25×) and obesity (1.2×) combine to 3× average mortality. That cuts expected remaining life from about 30.1 to roughly 19.3 years — close to 11 years lost.
Frequently asked questions
What is the average life expectancy in the US?+
According to final CDC data for 2024 (published January 2026), life expectancy at birth in the United States was 79.0 years overall — 76.5 for men and 81.4 for women — up 0.6 year from 2023 and above the pre-pandemic level.
Why does my life expectancy go up as I get older?+
Life expectancy at birth averages in everyone who dies young. Once you have survived to a given age, those early risks are behind you, so your expected age at death rises. A 65-year-old American man could expect 18.4 more years in 2024 — reaching about 83.4, well above the at-birth figure.
How much does smoking shorten life?+
Large studies in the US and UK found that people who keep smoking lose at least 10 years of life on average compared with never-smokers. Quitting before about age 40 avoids most of that excess risk, and quitting at any age helps.
How accurate is a life expectancy calculator?+
It can describe averages for people like you but cannot predict an individual lifespan. Genetics, existing illnesses, income, access to care and chance all matter, and the lifestyle adjustments here are simplified. Use it to compare scenarios, not to plan finances to an exact age.
What habits add the most years to life?+
Not smoking has the largest single effect, followed by regular physical activity, maintaining a healthy weight, limiting alcohol, a diet rich in plants and whole foods, and good sleep. Studies combining several healthy habits report gains of around a decade.
This tool gives general estimates and is not medical advice. Talk to a doctor or qualified professional about your health, diet or training.