How many seconds?
A typical year has 31,536,000 seconds (365 days). Leap years add a day—bumping that to 31,622,400 seconds. That’s a lot of ticking!
Big numbers
Birthday Countdown — Live Big Digits
Inputs
Countdown
Set your date of birth to begin.
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Days
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Hours
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Minutes
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Seconds
Next birthday: — · You’ll turn —
5 Fun Facts about Birthday Countdowns
Who celebrates first?
Birthdays arrive earlier for people near the International Date Line (like parts of Kiribati) and last for folks near it on the other side (like Baker Island). Time zones make parties chase the Sun!
Time zones
Leap-day birthdays
If you were born on Feb 29, non-leap years don’t have your exact date. Many celebrate on Feb 28 or Mar 1 — this tool’s default treats it as Feb 28.
Leap logic
Midnight matters
The countdown targets the moment your birthday starts (00:00 local time). You don’t need to wait for the party—midnight is the milestone!
Start of day
Longer or shorter birthdays?
With Daylight Saving Time, some birthdays are 23 hours long and others 25 (when clocks change). Your special day can literally stretch—or shrink—by an hour.
DST quirks
How it works
Choose your day, month, and year. The countdown updates every second. Birthdays on 29 February are treated as 28 February in non-leap years by default.
Tip: Share the countdown with friends using the “Copy sharable link” button — it encodes your DOB in the URL.