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.
How to use
- Pick your birthdate (or anyone's). It stays in this browser only.
- Watch the counter tick. The next five birthdays show below with their weekday.
- On the day itself, the page swaps to a confetti banner.
Frequently asked questions
- What's a 'golden birthday'?
- The year your age matches the calendar day you were born — born on the 17th, you have a golden birthday at age 17. People who were born on the 31st only get one between the ages of 28 and 31 depending on month, since not every month has a 31.
- Does it count leap-day birthdays correctly?
- Feb 29 births default to Feb 28 in non-leap years for the countdown — same rule most legal systems use. The exact-age math still uses the real Feb 29 anchor.
- Which time zone does the countdown run in?
- Your browser's own clock and zone, so it reaches zero at midnight where you are. Someone opening the same page in another country sees a different amount of time left, which is correct: a birthday is a calendar date rather than a single instant, and that date begins at a different absolute moment around the world.
- Why does the years-months-days age not match total days divided by 365?
- Because months differ in length and leap years add a day. Counting whole calendar years, then months, then the remaining days gives the age people mean when they say it out loud, while dividing total days by 365 — or by 365.25 — produces a decimal that drifts away from it by several days. Both figures are shown here because they answer different questions.
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