Birthday Countdown

Live-updates every second from the browser clock. Shows the days/hours/minutes/seconds remaining to the next birthday, the exact age right now in years-months-days, the total days alive, total hours lived, and the weekday of the next five birthdays so you can start booking. The golden birthday — the year your age equals your day-of-month — is highlighted with whether it's already happened or still coming.

Everything is computed against your device's clock and its current time zone, which is what makes the countdown feel right and also what makes it personal rather than absolute. Open the same page while travelling and the remaining time shifts by the offset between the two zones, because a birthday is a date on a local calendar rather than a moment in time. Someone born in Seoul and counting down in Los Angeles is looking at a different instant from the one their family is watching.

The years-months-days figure counts calendar units rather than dividing by an average, so it stays stable across leap years and months of unequal length. That is why the number of days in the same month-long stretch varies, and why two people the same age in years can show different day counts. The total days alive is a plain difference between dates and is the figure to use if you want something arithmetic.

A 29 February birth date has no anniversary in most years. Here the countdown, like the age figure, resolves it to 28 February in common years, which is one of two conventions in use; other jurisdictions treat 1 March as the legal date for age purposes, so a legal document may disagree with what this page shows.

A golden birthday falls at whatever age matches the day you were born on, so the date on the calendar decides how early it arrives. Born on the 5th, it was your fifth birthday and is long behind you; born on the 30th, it is still ahead for most people.