Find the weekday for any date — what day you were born, or any date in history or the future.
Pick your birth date above — the tool instantly shows the weekday, computed from the date with no time-zone surprises.
Yes, for any date your browser's date picker accepts, using the standard proleptic Gregorian calendar.
It's the position of the date within its year — January 1 is day 1, December 31 is day 365 (or 366 in a leap year).