What is the use of DAY function?

Returns the day of the month represented by a serial number.
Note:The day is given as an integer ranging from 1 to 31.

What is the syntax of DAY function?

DAY Function and Formula in Excel -syntax

DAY(serial_number)

Where serial_number: Is a number of the day
Serial_number is the date of the day you want to find.

DAY Function in Excel – Examples

DAY Function and Formula in Excel - Example

Reference:

Please refer the below article for more Date & Time Excel functions.
Date & Time Excel Formulas

Please refer the below article for more Excel Functions.
Excel Formulas | Home