What Day Was I Born Calculator

To find out what day of the week you were born on, simply enter your birth date into the calculator above. It uses a mathematical algorithm (Zeller's congruence or equivalent) to determine the exact day — Monday, Tuesday, Wednesday, etc. — for any date in history.

The calculator automatically counts how many days remain until your next birthday based on today's date. If your birthday has already passed this year, it calculates the days until your birthday in the following year.

Your zodiac sign is determined by the month and day of your birth. For example, if you were born between March 21 and April 19, your sign is Aries. The calculator identifies your sign automatically from your birth date.

Generations are defined by approximate birth year ranges: Gen Z (1997–2012), Millennials (1981–1996), Gen X (1965–1980), Baby Boomers (1946–1964), and the Silent Generation (1928–1945). The calculator identifies which generation you belong to based on your birth year.

Each month of the year has a traditional birthstone. For example, January's birthstone is Garnet, June's is Pearl, and December's is Turquoise. The calculator displays your birthstone based on your birth month.

Age is calculated by subtracting your birth date from today's date. The result is expressed in complete years, and the remaining time is broken down into months and days. The birthday is counted as the day the new year of age begins.

Yes — the day-of-week calculation works for virtually any historical date using standard calendar algorithms. Just enter any date and the calculator will return the correct day of the week, even for dates centuries ago, as long as they fall within the Gregorian calendar era.

The day number of the year tells you how many days into the year your birthday falls. For example, February 1 is day 32. This is also known as the ordinal date or Julian day number (within a given year).