Life Expectancy Calculator — How Long Will I Live?

Estimate your life expectancy from your age, sex and lifestyle — and see your projected lifespan. ⏳

Life Expectancy

Estimate your lifespan

Fill in your details for a lifespan estimate

How to Use the Life Expectancy Calculator

  1. Enter your age and sex.
  2. Answer a few lifestyle questions — smoking, exercise and diet have the biggest impact.
  3. See your estimated lifespan and how many years that suggests you have ahead.

What Affects Life Expectancy?

In the US, average life expectancy at birth is roughly 76 years for men and 81 for women. But averages aren't destiny — lifestyle choices shift the number significantly. Smoking can cut a decade off your life, while regular exercise, a healthy diet, good sleep and low stress can add many healthy years. This calculator starts from population baselines and adjusts for the lifestyle factors with the strongest evidence.

Treat the result as a motivational ballpark, not a prediction. The encouraging part: the biggest levers — not smoking, staying active and eating well — are largely within your control, and improving them at any age still pays off.

Formula & Logic

Life expectancy figures are period estimates drawn from actuarial tables — they describe the average remaining years for people of a given age and sex under current mortality rates, not a prediction for any individual. The most misunderstood property is that expectancy rises with age: a newborn's life expectancy is lower than the age a 70-year-old can expect to reach, because the newborn's figure is dragged down by everyone who dies before 70. That is why retirement planning should use expectancy conditional on reaching retirement, not expectancy at birth.

Expected age at death = current age + remaining life expectancyRemaining expectancy is read from a mortality table by age and sexConditional expectancy rises with attained agePlanning horizon: use the 75th or 90th percentile, not the mean

where:

period table
assumes current mortality rates persist; cohort tables project improvement
conditional
expectancy given you have already reached a certain age
percentile
half of people outlive the mean — plan beyond it

Assumptions: Population averages that take no account of individual health, family history, smoking, income or occupation, all of which shift outcomes substantially. Not a medical prognosis.

Step-by-Step Example: Why a 65-Year-Old Should Not Plan to 79

Compare expectancy at birth with expectancy conditional on reaching 65.

  • Life expectancy at birth≈79 years
  • Remaining expectancy at 65≈19 years
  • Current age65
  1. Naive reading: expectancy at birth is 79, so plan for 14 more years.
  2. Correct reading: having reached 65, remaining expectancy is about 19 years.
  3. Expected age at death: 65 + 19 = 84, not 79.
  4. The five-year gap exists because early deaths no longer apply to you.
  5. But half of 65-year-olds will live beyond 84 — the mean is not a safe planning target.
  6. Planning to the 90th percentile means budgeting to roughly age 95, or 30 years.

ResultA 65-year-old should plan to about 95, not 79

That 16-year difference between the naive and the prudent planning horizon transforms a retirement calculation. It is also why a 4% withdrawal rate, tested over 30 years, is the convention: 30 years is the realistic planning horizon from 65, not the 14 that expectancy at birth would suggest.

Life Expectancy FAQ

It's a simplified estimate based on population averages and major lifestyle factors. It can't account for genetics, medical history or chance, so use it for motivation rather than as a medical forecast.
On average women outlive men by about 5 years, due to a mix of biological and behavioural factors. The calculator reflects this baseline difference.
Yes — quitting smoking, exercising regularly and eating well are strongly linked to longer, healthier lives, and the benefits start at any age.

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✔ Written & reviewed by Dr Sam — 20+ yrs in management & research leadership📅 Last updated June 2026📚 Sources: CDC & USDA / HHS Dietary Guidelines📑 How we build & check these⚖ General information only — not medical advice