Day of the Week
What weekday a date falls on — and in the years around it.
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Any date from year 1 to 9999. The proleptic Gregorian calendar is used throughout, so dates before its adoption are extrapolations rather than what people alive then would have written.
Enter a date to look up its day of the week.
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How to use it
Enter any date to see what day of the week it falls on, plus its week number, day of the year, and its weekday in the years around it.
Enter any date — your birthday, a wedding, a date in history — and see what day of the week it falls on.
The table shows the same date over several years, which answers the questions people really ask: “When does my birthday next fall on a Saturday?” or “Which year does our anniversary land on a weekend?”
Why does your birthday move? A normal year is 52 weeks and one day, so dates shift forward one weekday each year — and two after a leap day.
You’ll also see the ISO week number and the day of the year. For repeating dates like every third Tuesday, use Recurring Dates.
FAQ
What day of the week was I born on?
Enter your date of birth and the weekday appears straight away.
Why does my birthday land on a different day each year?
A year is 52 weeks and one day, so it moves forward one weekday — two after a leap day.
How far back does it go?
Year 1 to year 9999. Very old dates use today’s calendar rules, so they may not match records from the time.
What is the ISO week number?
A week count where weeks start on Monday and week 1 contains the first Thursday of January.
When will this date next be on a weekend?
Check the table of nearby years.
How it worksFor the curious
Weekdays are computed directly from the date on the proleptic Gregorian calendar — modern rules extended backwards. Britain and its colonies switched from the Julian calendar in September 1752, skipping eleven days, and most of Catholic Europe in 1582, so weekdays before the local switch will not match contemporary records. Years 1 to 9999 are supported.
ISO weeks start on Monday, and week 1 is the week containing the first Thursday of January, so early January dates can belong to week 52 or 53 of the previous year.
Without a century adjustment, the weekday pattern repeats every 28 years. To count days between dates instead, use the date difference calculator.