How to Use the Day of the Week Calculator
Ever wondered what day of the week a historical event happened on, or which weekday your upcoming anniversary falls on? This calculator instantly finds the day of the week for any year, month, and day you enter, based on the Gregorian calendar. It also compares the date to today, showing how many days ago it was or how many days remain.
It's handy for checking what day you were born, which weekday a wedding anniversary or project deadline lands on, or spotting the 7-day repeating pattern that shifts a given date's weekday by one (or two, across leap years) each year.
The calculation relies on your browser's standard date handling and is most accurate for dates after October 15, 1582, when the Gregorian calendar was officially adopted. Earlier dates may not match historical records exactly, since the Julian calendar was in use before that point — treat those results as a reference only.
Frequently Asked Questions
Yes, it uses the Gregorian calendar, so any past or future date works. Dates before 1582 may not match historical records, since the calendar system in use back then was different.
Just enter your birth date and the result will show the day of the week along with how many days have passed since then, or how many days until it comes around again.