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A birthday calculator computes your exact age in years, months, days, hours, and even seconds. It can also calculate how many days until your next birthday, what day of the week you were born, and your star sign.
ステップバイステップガイド
- 1Subtract the birth date from today's date
- 2Handle leap years (Feb 29 birthdays fall on Mar 1 in non-leap years)
- 3Days until next birthday = Next birthday date − Today's date
解いた例
入力
Born 15 March 1990 · Today 15 March 2026
結果
Exactly 36 years old
36th birthday today
入力
Born 29 Feb 2000 · Today 1 Jan 2026
結果
25 years, 306 days
Leap-year birthday calculation