Day of Week Calculator
Find which day of the week a date falls on.
Worth Knowing
Finding the weekday for any date relies on the fact that the calendar repeats in a fixed, computable pattern — the algorithm behind this is a cousin of the mental-math 'Doomsday rule' that lets people name weekdays for arbitrary dates. It's genuinely useful for planning around historical or future dates, checking which anniversaries fall on weekends, or settling the perennial question of what day you were born on. The Gregorian calendar's full cycle repeats every 400 years.
How to Use
- Enter Date into the Day of Week Calculator above.
- Your result appears instantly as you type — there's no submit button or page reload.