How is age calculated?

We compare birth date to the target date and compute years, months, days and total days, weeks, hours, minutes.

Can I use a past or future date?

Yes. Set 'Calculate as of' to any date.

Yes. Your animal sign is shown based on birth year.

计算您的精确年龄（年、月、日）。总天数、周数、小时和分钟。下次生日与星座。

出生日期计算至

输入出生日期以计算

How is age calculated exactly?: Age is calculated by comparing the birth date to the target date. We compute years, months, days and total days, weeks, hours, minutes. All in your browser.
How do I calculate age between two specific dates?: Use the 'Calculate as of' date field and set it to the end date. The calculator shows age on that date.
What is the difference between age in years vs total days?: Age in years, months and days is calendar age. Total days is the exact number of days between the two dates.
Which generation am I if I was born in 1990?: 1990 is Millennial (1981–1996). The calculator uses standard ranges: Baby Boomer, Gen X, Millennial, Gen Z, Gen Alpha.
How is the zodiac sign determined?: Based on birth month and day using the tropical zodiac (Aries, Taurus, etc.).
What is the Chinese zodiac and how is it calculated?: Chinese zodiac has 12 animals in a 12-year cycle. Your sign depends on birth year. Formula: (year − 1900) mod 12.
How many days have I been alive?: The Total Days card shows the exact number of days between birth date and the target date, including leap years.
Is this age calculator accurate for leap year birthdays?: Yes. The calculation uses the actual calendar and counts real days, so leap years are handled correctly.