Online Timer
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Half Birthday Calculator
Find the date six months after your birthday.
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your next half birthday
How a half birthday is calculated
Your half birthday is the same day number six calendar months after your birthday: June 15 becomes December 15. When that month is too short, it moves to the month's last day. Birthdays on August 29, 30, or 31 have a half birthday on February 28, or February 29 in leap years. March 31 becomes September 30, and May 31 becomes November 30.
The exact midpoint splits the days between two birthdays in half instead (182 or 183 days after your birthday), so it can be a day or two away from the six-month date. Kids with summer birthdays often celebrate at school on their half birthday.
Frequently asked questions
When is the half birthday for August 31?
February 28, or February 29 in a leap year. February has no 30th or 31st, so the half birthday moves to the last day of the month.
Is a half birthday exactly 182.5 days?
Not quite. The usual half birthday is six calendar months later. The calculator also shows the midpoint day, which splits the year between birthdays evenly.
What if I was born on February 29?
Your half birthday is August 29 every year, so unlike your birthday it never skips a year.
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