Time & Date
Birthday Countdown Calculator
Count the days until the next birthday from a birth month and day.
This result is the number of whole days until the next birthday, and the date in brackets is the date of that next birthday.
Formula
Next birthday = this year's birth month and day, or next year's if that date has already passed this year. Days remaining = next birthday minus today.
How it works
Enter the birth month and day, plus today's date. The calculator finds the next occurrence of that birthday and counts whole days to it, so you can plan ahead without doing calendar arithmetic.
Worked example
For example, for a birthday on 15 June with today set to 28 October 2026, the next birthday falls on 15 June 2027, which is 230 days away.
FAQs
Does it need the birth year?
No. Only the month and day matter for the next birthday, so the year is left out.
What about 29 February birthdays?
In non-leap years the date rolls to 1 March in this calculator's calendar arithmetic; many people celebrate on 28 February instead — either way the count is within a day.
What if the birthday is today?
The result is 0 days, with a birthday message.
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