Day of the week calculator
Enter your date of birth to see the weekday you were born on and your current age.
What day of the week was I born?
This tool tells you which day of the week (Monday, Tuesday…) any date falls on — for example the day you were born. Just enter the date and get the answer instantly, with no sign-up.
How the day of the week is found
Every calendar date has a fixed, computable weekday. Methods such as Zeller’s congruence or Conway’s Doomsday rule work out the day from the day, month and year without needing a calendar. Your browser uses the Gregorian calendar to give the exact answer.
A curious pattern
The Gregorian calendar repeats exactly every 400 years. Also, your birthday moves forward one weekday each year (two when a 29 February falls in between), so it rarely lands on the same day two years running.
Frequently asked questions
What day of the week was I born? Enter your date of birth and the tool gives the exact day.
Does it work for future dates? Yes, for any past or future date in the Gregorian calendar.
Why does my birthday change weekday each year? Because 365 days is 52 weeks plus 1 day, so the date shifts one weekday (or two after a leap day).