Weekday Calculator
Find the day of the week for any date, plus its day of year, ISO week number and weekend status.
Find the weekday for any date
Also see the date's day-of-year and ISO week number.
What day of the week was a date?
Select a date and the calculator will show whether it falls on Monday, Tuesday, Wednesday, Thursday, Friday, Saturday or Sunday. It also provides the day number within the year and ISO week number for extra context.
This can help with historical schedules, anniversaries, project records, recurring-event planning and simple calendar questions.
Check a date with known examples
| Date | Weekday | Day of year |
|---|---|---|
| January 1, 2000 | Saturday | 1 |
| February 29, 2024 | Thursday | 60 |
| September 22, 2026 | Tuesday | 265 |
Day of year counts January 1 as day 1. It reaches 365 in an ordinary year and 366 in a leap year. The result's weekend label means Saturday or Sunday; it does not infer your employer's workweek.
Calendar assumptions and related tools
The calculator uses the Gregorian calendar, including when looking backward in time. It does not reproduce each country's historical switch from the Julian calendar. For historical records, first establish which calendar the original date used.
If you need a numbered week and its Monday–Sunday boundaries, use the ISO Week Number Calculator. To exclude a custom weekend from a date range, use Business Days. To move a date forward by a number of days, use the Date Calculator.