Day of the Week Calculator
Find a Gregorian date’s weekday, day number within its year and leap-year status.
Your result
EVERYDAYEnter your values and select calculate.
On this page How it works & practical examples
How to use the Day of the Week Calculator
Select a complete calendar date to find its weekday. The day-of-year number treats January 1 as day one and increases through the year, including February 29 in a leap year. The field starts with your device’s current date and can be changed to another supported date. UTC date arithmetic keeps the answer independent of local daylight-saving transitions.
The calculation
Worked example
January 1, 2026 falls on a Thursday and is day 1 of a non-leap year. February 29, 2024 falls on a Thursday in a leap year.
Assumptions and limits
This page uses the Gregorian calendar and supports dates from 1900 to 9999. It does not convert time zones or handle historical adoption differences between calendar systems. A date is not a timestamp, so the tool does not ask for a clock time or location. Invalid dates are rejected instead of silently rolling into another month.
Common questions
Does the answer depend on my time zone?
The selected calendar date’s weekday does not. The initial “today” value comes from your device’s local date.
How is a leap year recognized?
The Gregorian rule includes years divisible by four except centuries not divisible by 400.