Your birthday
Age is counted in completed years. The zodiac animal follows the calendar year.
Age in days rather than years
Years round away most of a life. Counting the days you have actually lived gives a number that moves every morning and makes round milestones — ten thousand days, twenty thousand — land somewhere other than a birthday.
Born on a leap day
A 29 February birthday has no anniversary in three years out of four. This tool moves the countdown to 1 March in those years, which is the common convention but not a universal one — some jurisdictions use 28 February for legal purposes.
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Frequently asked questions
Q. How is age counted here?
By completed years since birth, the convention used almost everywhere. You turn one on your first birthday, not at birth.
Q. Why does the day of the week matter?
It does not, particularly — but people are curious, and the answer is not something you can work out in your head. Weekdays repeat on a 400-year cycle, so the same date falls on the same weekday 400 years apart.
Q. What are the two signs?
The Western zodiac sign from the date within the year, and the East Asian zodiac animal from the year itself, on a twelve-year cycle. The animal here follows the calendar year rather than the lunar new year, so dates in January and early February may differ from a lunar calendar.