Age Calculator
Calculate your exact age and days until your next birthday
Precise Calculation
Accurate to the day
Birthday Countdown
Days until celebration
Frequently asked questions
Does the calculator account for leap years?
Yes, indirectly. The age is computed using JavaScript Date arithmetic on calendar fields, so a February 29th birthday and the extra day in leap years are handled by the date's own day math rather than a fixed 365-day assumption.
Why does the "months" figure not match dividing my total days by 30?
The years/months/days breakdown compares calendar fields directly (year, month, day) rather than dividing a day count by 30. When the day-of-month has not yet been reached, a month is borrowed and filled in with however many days that previous month actually has, so the numbers reflect real calendar months, not fixed 30-day blocks.
What does the "Japanese age" toggle actually show?
It is a simplified version of the traditional kazoe-doshi system: current year minus birth year, plus one, since you are counted as 1 year old at birth. It does not check whether your birthday has passed yet this year, so it typically reads one year higher than your standard age and does not follow the traditional New Year's Day rollover exactly.
How is "days until next birthday" calculated if today is my birthday?
The calculator builds this year's birthday date and compares it to today; it only rolls forward to next year once today is strictly past that date. On your actual birthday, the difference is 0 days.