How to use
- Enter your date of birth in the calendar you know; the age is calculated up to today in the time zone of the city selected on the site.
- For the span between any two other dates, use the Duration tab.
Reading the results
- At the top: the total days you have lived and the weekday you were born on.
- Then one card per calendar, in the standard order: your age in it (years, months, days), your date of birth in it, and your next birthday in it with the days left.
Why does the age differ between calendars?
- A lunar year (354–355 days) is about 11 days shorter than a solar year, so the Hijri age gains a full year roughly every 33 solar years.
- Years of The Creator's Calendar follow the solar year on average thanks to Al-Nasi, so the age in it is close to the Gregorian age; its remaining months are counted as real lunar months.
- The Hebrew year is lunisolar like The Creator's Calendar, so the age in it is close to the Gregorian age, but its leap months follow a fixed 19-year cycle rather than the season. The Chinese calendar is lunisolar too, with its leap months set by the solar terms.
- The Julian age usually equals the Gregorian age, but the birthday falls on the Julian date (2 March Julian = 15 March Gregorian today).
Birthdays in special cases
- Born on 29 February: the birthday in a common year is 28 February. Likewise day 30 of a lunar month that has 29 days, or 30 Esfand in a common Solar Hijri year: the month's last day is used.
- The Creator's Calendar: the birthday is in the same month by name every year — except for those born in Al-Nasi, whose birthday follows the month number: born in Al-Nasi as the 5th month means a birthday in the 5th month every year, whether or not it is Al-Nasi (3 Al-Nasi 1404 → 3 Jumada al-Ula 1405).
- Hebrew, by the rule in Jewish use (Shulchan Aruch, Orach Chaim 55, as computed by Hebcal): someone born in Adar of a common year or in Adar II celebrates in the last month of the year (Adar, or Adar II in a leap year); someone born in Adar I celebrates in Adar I in a leap year and in Adar in a common year; someone born on the 30th of Cheshvan, Kislev or Adar I celebrates, in a year without that day, on the 1st of the next month (not the 29th).
- Chinese, by Chinese custom: the birthday is on the same month number and day every year; someone born in a leap month celebrates in that leap month if the year has it, otherwise in the regular month with the same number; someone born on the 30th celebrates on the 29th when the month has 29 days (the month's last day).
Your birth in the sky
- Below the results, a card shows where the Sun and Moon were on your birthday, computed astronomically from the ephemeris: the tropical sign (twelve equal signs from the March equinox), the astronomical sign (the constellation actually behind the Sun, by IAU boundaries), the Chinese zodiac and its element, the Moon phase and illumination, and the lunar mansion and the Sun's nawʾ in both the sidereal and equal systems.
- The Chinese zodiac follows the Chinese year, not the Gregorian one: someone born in January or early February before the Chinese New Year has the previous year's animal.
- A birth date has no hour, so when the sign, mansion or nawʾ changes during that day both are shown as “before → after” with the moment of change in your city's time; pick the one matching your birth hour.
- Astronomical information only; the site shows no predictions.
Born 15 March 1990 in Riyadh: the Sun in Pisces in both systems, the Chinese sign Horse (Metal · 庚午), the Moon waning gibbous at 86% illumination, its sidereal mansion Al Ghafr → Al Zubana at 14:06, and its equal mansion Al Iklil → Al Qalb at 12:37.
Example
Born 15 March 1990, calculated on 18 October 2026: 36 years, 7 months and 3 days Gregorian, 37 years, 8 months and 19 days Hijri, 36 years, 7 months and 19 days in The Creator's Calendar, and 36 years, 7 months and 19 days Hebrew (born 18 Adar 5750, so the next Hebrew birthday is 18 Adar II 5787), and 36 years, 6 months and 19 days Chinese (born on day 19 of Month 2, 1990, a year of the Horse); 13,366 days lived in total, and the next Hijri birthday is 18 Sha'ban 1448 (in 100 days).