Retrieves the day of the week from a given date

`=WEEKDAY(serial_number,[return_type])`

- serial_number - required, the date to get the weekday from
- return_type - [OPTIONAL] a number that says how to map the week

`=WEEKDAY("3-Jan-21")`

This function returns returns 1 for Sunday, the numerical equivalent of the day of the week provided in the Date Argument. The first argument of the WEEKDAY function is the Date, which is "3-Jan-21" in this example. The second argument is optional and is set to 1 if omitted, which indicates that the week starts on Sunday.

`=WEEKDAY("4-Jan-21")`

This function returns 2 for Monday. The first argument is the Date, which is "4-Jan-21" in this example. The second argument is still set to 1, which indicates that the week starts on Sunday. The result of the function is 2 for Monday, as the week begins on Sunday.

`=WEEKDAY("3-Jan-21",2)`

This returns 7 for Sunday. This example is similar to the previous one, but the second argument has been changed to 2. This indicates that the week should start on Monday, so the result of the WEEKDAY function is 7 for Sunday, as Monday is the first day of the week.

`=WEEKDAY(B5)`

This returns Sunday as the weekday of the date in B5. This example shows how the WEEKDAY function can be used to return the day from a date in a cell

The WEEKDAY function provides an easy way to determine the day of the week for a given date, returned as a number from 1 to 7.

- The WEEKDAY function takes a date as its argument and returns a number that represents the day of the week.
- The WEEKDAY function may be nested in other formulas for checking the day of the week.
- By default, WEEKDAY returns 1 for Sunday and 7 for Saturday. However, you may use the return_type argument to control the weekday numbering system.
- If the date is empty, WEEKDAY returns a value of 7.

The WEEKDAY function is a Sourcetable function that returns an integer representing the weekday of a date.

The WEEKDAY function can be useful in financial analysis. For example, it can be used to calculate how long it takes to complete projects.