DAY

Returns the day of a given date.

Syntax:

DAY(date)

returns the day of date as a number (1-31). date may be text or a date-time serial number.

Example:

DAY("2021-12-04")

returns 4.

DAY(A1)

where cell A1 contains the date 23 Nov 2021 as a date-time serial number, returns 23.

Application:

Tracking Project Milestones

Imagine you're a project manager, and you need to keep track of various project milestones and their completion dates. You're particularly interested in knowing the day of the month each milestone was completed, perhaps for reporting or to identify any patterns related to the time of the month.

Table: Project Milestones

	Project ID	Milestone Name	Completion Date	Day of Month
	A	B	C	D
1	P101	Requirements Approved	1/15/2025	15
2	P102	Design Complete	2/28/2025	28
3	P103	Development Start	3/10/2025	10
4	P104	Testing Phase Initiated	4/5/2025	5
5	P105	Client Sign-off	5/22/2025	22
6	P106	Deployment	6/1/2025	1
7	P107	User Training Complete	7/31/2025	31

When the DAY function is applied to each date in the "Completion Date" column, it extracts only the numerical day of the month from that specific date. For example:

For "2025-01-15", the DAY function returns 15, as January 15th is the 15th day of the month.
For "2025-02-28", the DAY function returns 28, as February 28th is the 28th day of the month.
For "2025-03-10", the DAY function returns 10, as March 10th is the 10th day of the month.
For "2025-04-05", the DAY function returns 5, as April 5th is the 5th day of the month.
For "2025-05-22", the DAY function returns 22, as May 22nd is the 22nd day of the month.
For "2025-06-01", the DAY function returns 1, as June 1st is the 1st day of the month.
For "2025-07-31", the DAY function returns 31, as July 31st is the 31st day of the month.

The results in the "Day of Month" column are thus a simple integer representing the day component of each corresponding completion date.