How It Works

Data sources

All numbers come from the World Health Organization’s Global Health Observatory (GHO), retrieved through its public OData API on 2026-10-06. The latest year available is 2023, covering 185 countries.

• Life expectancy at birth (years), indicator WHOSIS_000001, by country and sex: https://ghoapi.azureedge.net/api/WHOSIS_000001
• ex – expectation of life at age x (the WHO life tables), indicator LIFE_0000000035, by country, sex and age group (under 1, 1–4, 5–9 … 80–84, 85+): https://ghoapi.azureedge.net/api/LIFE_0000000035
• Country names and WHO regions: https://ghoapi.azureedge.net/api/DIMENSION/COUNTRY/DimensionValues
• Background: WHO Global Health Estimates: life expectancy and healthy life expectancy

The data is baked into the site when it is built, so your browser never contacts the WHO or any other server to calculate. Values are shown exactly as published, rounded to one decimal place.

Attribution: World Health Organization 2023 data, Global Health Observatory: “Life expectancy at birth (years)” and “ex – expectation of life at age x” [indicators], https://ghoapi.azureedge.net/api/WHOSIS_000001 and https://ghoapi.azureedge.net/api/LIFE_0000000035 (accessed 2026-10-06). Licensed under CC BY 4.0. Clock of Life is not affiliated with or endorsed by the WHO.

The method, step by step

1. Exact age. From your birth date we calculate your age in years, to the day (using an average year of 365.2425 days).
2. Remaining life expectancy. The WHO life table gives the average remaining years, e_x, at the start of each age group: 0, 1, 5, 10 … 85. For an age between two of these points we interpolate linearly.
3. Estimated lifespan. Expected age = your age + remaining years. Today’s date plus the remaining years gives the date you would reach it.
4. Your time ahead. The life clock shows the time from now to that date in years, days, hours, minutes and seconds.

Worked example

A woman in the United States aged 37.5: the WHO 2023 table gives 47.11 remaining years at age 35 and 42.41 at age 40. Halfway between is 44.76 years, so her expected age is 82.3 which she would statistically reach 44.8 years from today.

Ages 85 and over

The WHO tables end with an open age group, 85 and over. For anyone 85 or older we show the average remaining life for that whole group and say so in the result. For people well above 85 the true average is lower, so treat it as an upper reference.

What these numbers mean, and what they don’t

A life table is a period measure: it applies the chances at every age in one year (2023) to a whole lifetime. It does not include future medical progress or changes in how people live, which have raised life expectancy almost everywhere over time. It describes populations, not individuals, and it only knows age, sex and country.

That is why every calculator carries the line “For entertainment and statistics only – not a medical prediction.” The site is not medical advice and makes no claims about your health or your biological age. We deliberately do not offer habit sliders (smoking, exercise and so on): we would only add them if each adjustment could be backed by a published estimate cited here, and we prefer no number to an invented one.

Privacy

All calculations run in your browser. Your birth date, age, sex and country are never stored, never sent to a server and never put in the page address. We count anonymous, aggregated page views with cookie-free Cloudflare Web Analytics; see privacy.