How it works

By Your Age lines up your exact age against dated moments in real lives. It is a selected sample of remarkable people, chosen for well-documented dates. It is not a forecast, a score or a verdict on anyone's life.

Methodology: age in elapsed calendar days

Your age is the number of calendar days from your birthday to today, using your device's own calendar date. Every date is turned into a whole-number day count on the Gregorian calendar, so time zones and daylight saving never shift the result. The "as of" date shown with your result is frozen when you press Place me.

"The same age" means the same number of elapsed calendar days, not the same years, months and days. Two people can be "31 years and 0 days" old with different day counts, because one of them lived through more 29 Februaries.

The years-and-days label counts whole birthdays passed, then the days since the last one. If you were born on 29 February, your birthday counts as 1 March in years that are not leap years.

Placing a milestone

• Had already: the latest possible date of the event was on or before your day count.
• Still ahead: the earliest possible date was after your day count.
• Too broad to place: the event is known only to a month or a year, and that window spans your age. We say so rather than guess.
• Exactly your age appears only when an event known to the exact day happened at your exact day count.

A year-only date is treated as the whole year, never as 1 January. Award milestones use the year the prize was decided, which is not the same as the ceremony. Death is never a milestone.

How people were chosen

People span writing, music, film, art, science, exploration, aviation, sport, business and public life, with milestones from their teens to their eighties, so most adult ages fall between something already done and something still to come. Everyone included has an unambiguous, day-precision Gregorian birth date. Captions are written for this site from the cited facts.

Sources and licences

Birth and death dates were checked against Wikidata, whose structured data is released under CC0. We credit it anyway, with thanks. Each milestone links to at least one specific supporting page, such as NobelPrize.org or the relevant Wikipedia article; open "Sources and dates" under any milestone to see them along with the calculation. No text or images are copied from those pages.

The typeface is Archivo by Omnibus-Type, used under the SIL Open Font License.

Privacy

Your birthday never leaves your browser. It is not sent to our server, not put in the address bar, not stored on your device and not logged. The page downloads the same list of lives for everyone and does all the arithmetic locally. "Copy comparison" copies your age in days and the facts on screen, never your birth date.

There are no accounts, cookies, analytics or third-party requests. Our server does not log your visits. It records only its own errors (the page path and the error), which can never contain your birthday because the birthday is never sent.