Life expectancy is the average number of years a person can expect to live, calculated from birth or from a specific age. Globally, life expectancy reached 73.1 years in 2019 before the COVID-19 pandemic pushed it back to 71.4 years by 2021. In the United States, it stood at 79.0 years in 2024, with women averaging 81.4 years and men 76.5 years.
How Life Expectancy Is Calculated
The number you typically see reported is called “period life expectancy.” It takes the death rates for every age group in a single year and uses them to estimate how long a newborn would live if those rates never changed. It’s a snapshot of current conditions, not a prediction of any individual’s future.
There’s a second, less commonly reported version called “cohort life expectancy.” Instead of freezing mortality rates at one point in time, it follows an actual birth year group forward, incorporating real improvements in medicine, safety, and public health as they happen. Because healthcare and living conditions tend to improve over time, cohort life expectancy runs significantly higher. In England and Wales, cohort life expectancy at birth is typically seven to eight years longer than the period figure. So when you see a headline saying life expectancy is 79 years, the real outlook for a baby born today is likely better than that.
Why the Historical Numbers Look So Low
You’ve probably seen claims that people in past centuries only lived to 30 or 40. Those numbers are technically accurate averages, but they’re heavily dragged down by infant and childhood deaths. Once you strip out deaths before age five, the picture changes dramatically. In mid-Victorian England, for example, a child who survived to age five could expect to live to about 75 if male and 73 if female. That’s not far from modern figures. The enormous gains in average life expectancy over the past 150 years are largely about keeping children alive through their first years, not about extending old age by decades.
The Gender Gap
Women outlive men in virtually every country on Earth. In the U.S. in 2024, the gap was about five years: 81.4 for women versus 76.5 for men. This difference comes from a combination of biology and behavior. Women appear to have a baseline biological advantage, possibly related to hormonal protection against cardiovascular disease and genetic benefits from carrying two X chromosomes. Men, meanwhile, have historically faced higher rates of death from occupational hazards, violence, and risk-taking behavior.
The gap has been narrowing in recent decades as differences in lifestyle between men and women shrink and as cardiovascular death rates among men decline. At the highest income levels in the U.S., the gender gap drops to just 1.5 years, suggesting that when men have full access to healthcare and lower-risk living conditions, much of the behavioral disadvantage disappears.
Income and Where You Live
Few factors predict life expectancy as powerfully as income. A landmark study published in JAMA found that the richest 1% of Americans lived roughly 15 years longer than the poorest 1% among men, and about 10 years longer among women. That gap is larger than the difference between the U.S. and many developing nations.
Geography matters even within the same income bracket. Low-income residents in wealthy cities with strong public health infrastructure, less exposure to smoking, and better access to parks and healthy food live measurably longer than low-income residents in poorer regions. The built environment, including proximity to fast food, walkability, and social connectedness, shapes health behaviors in ways that compound over a lifetime.
How Countries Compare
Among wealthy nations, life expectancy varies more than you might expect. As of 2024, Switzerland leads at 84.2 years, followed closely by Japan at 84.1 and Sweden at 83.8. Australia and France both come in around 83.0 years. The United States, despite spending far more on healthcare per person than any other country, sits at 79.0 years, trailing peer nations like Germany (81.2), the United Kingdom (81.3), and the Netherlands (81.9).
Years Lived in Good Health
Living longer doesn’t automatically mean living well. The World Health Organization tracks a separate metric called healthy life expectancy, which counts only the years a person lives in good health, free from serious disability or disease. Globally, healthy life expectancy was about 62.8 years in 2020, compared to overall life expectancy of 72.5 years. That means the average person spends roughly the last decade of life dealing with significant health problems. The goal of public health isn’t just to add years but to close that roughly 10-year gap between total lifespan and healthy lifespan.
Where Life Expectancy Is Headed
Global life expectancy is projected to rise from 73.6 years in 2022 to 78.2 years by 2050, according to research published in The Lancet and reported by The BMJ. The gains will come largely from continued progress against infectious diseases, improvements in maternal and newborn care, and better treatment of conditions like heart disease and diabetes. At the same time, rising rates of obesity and metabolic disorders are expected to partially offset those gains, shifting the global disease burden further toward chronic, long-term conditions rather than acute infections.
In the U.S., the trend is currently positive again after pandemic-era declines. Life expectancy rose 0.6 years between 2023 and 2024, with men gaining 0.7 years and women gaining 0.3 years. For a 65-year-old American in 2024, remaining life expectancy was 19.7 years, meaning the average person reaching retirement age can expect to live into their mid-80s.