Day of Week Calculator
Find out what day of the week any date falls on.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
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Request a ToolHow to Use the Day of Week Calculator
Select any date and the calculator instantly tells you what day of the week it is or was, along with whether it is a weekday or weekend.
- Pick a date. The calculator defaults to today but accepts any date, past or future.
- See the result. The day name is shown in large text. A badge shows whether the date is a weekday or weekend day.
- Copy or share. Use the Copy button to copy the result as text, or Share to send a link with the date pre-filled.
About the Day of Week Calculator
The Gregorian calendar algorithm used here is accurate for any date from the adoption of the Gregorian calendar (1582 in most of Europe, later in other regions) through the far future. For historical dates before the Gregorian calendar was adopted, results reflect the proleptic Gregorian calendar, which projects the calendar backward as if it had always been in use.
Common uses include verifying whether a historical event fell on a specific day, checking what day a birthday or holiday falls on in a future year, and confirming the day of week for scheduling purposes.
Frequently Asked Questions
What day of the week was July 4, 1776?
July 4, 1776 was a Thursday. You can verify this by entering 1776-07-04 in the calculator. The United States Declaration of Independence was signed on a Thursday.
What day will January 1, 2030 fall on?
January 1, 2030 will be a Tuesday. Enter 2030-01-01 in the calculator to confirm. You can use the calculator to plan any future date to check if a target date falls on a weekday or weekend.
How accurate is the day of week calculation for very old dates?
The calculation uses the proleptic Gregorian calendar, which projects today's calendar system backward in time. For dates after October 15, 1582 (when the Gregorian calendar was first used) this is accurate for countries that had adopted it by then. For dates before 1582 or in regions that adopted the Gregorian calendar later, the historical calendar in use at the time would have given a different day.
What is the difference between a weekday and a business day?
A weekday is any day from Monday through Friday. A business day is typically a weekday that is not a public holiday. This calculator identifies weekdays and weekends but does not account for holidays. For business day calculations that need holiday exclusions, consult a calendar for your specific region.