Day of the Week
Find out which day of the week any date falls on — a date in the past, today, or a date in the future.
How the calculation works
The calculator uses the Gregorian calendar — the calendar used in most of the world today. Weekdays repeat every 7 days, so the weekday of any date can be worked out by counting forward or backward from a known reference day, taking leap years into account.
For dates before 15 October 1582, the calendar is extended backwards — this is called the "proleptic" Gregorian calendar. It may differ from the Julian calendar that was actually in use at the time, so very old historical dates should be double-checked against a historical source.
Worked example
14 November 2026 is a Saturday. It is day 318 of 2026. Another date you can check: 1 January 2000 was also a Saturday — the first day of the 21st century's first year fell on a weekend.
Frequently asked questions
How far back or forward can I go?
The calculator works with dates from year 1 to year 9999. For dates before 1582, see the note above about the proleptic Gregorian calendar.
What happened to the calendar in 1582?
Pope Gregory XIII reformed the Julian calendar to fix a drift against the seasons. Ten days were skipped — Thursday 4 October 1582 was followed directly by Friday 15 October 1582 — and the leap-year rule was changed. Different countries adopted the change at different times over the following centuries.
Does my time zone change the answer?
No. The day of the week is a property of the calendar date itself, not of the time of day or where you are.
Why is this useful?
Common uses are planning events and anniversaries, checking what weekday a birthday or holiday falls on in a future year, and looking up the weekday of a date from family history or old documents.
What else does the calculator show?
As well as the weekday, it shows the day number of the year — for example, 14 November 2026 is day 318 of 2026 — and how many days away the date is from today.
Related tools
- Age Calculator — how old are you, in years, months and days?
- Days Between Dates — count the days between any two dates.
- Days Until — Countdown — count down to a future date.
- Add or Subtract Days — what date is N days from now?