The DAY function is a simple date function that extracts just the day from a given time. If you are working with times, but only care about the day, the DAY function lets you get rid of everything else.

Before reading the examples below, ensure you know how dates and times work. If you simply use a "1" as a value, Sheets doesn't know if it is 1 day, 1 month, etc.

Purpose

The DAY function returns the value of the month from any given unit of time.

Video Explanation

Syntax

=DAY(time)

Examples

Example 1 - Plain and Simple

A few simple examples of the DAY function.

FormulaDescriptionResult
=DAY("1/2016")Extract the day value from 1/2016.1
=DAY("1/31/2016")Extract the day value from 1/31/2016.31
=DAY("1")Extract the day value from 1.31

Tip: The DAY function shows its eccentricity when trying to convert the number 1 to a day. It helps to see the table below and keep in mind how dates and times work to make a little sense out of this.

Example 2 - Separating the values of a date and time.

Different date values examined using various functions.

Time valueTickmarkYEARMONTHDAYHOURMINUTESECONDFormatted as number
7/30/20161201673000042,581.00
7-30-20162201673000042,581.00
6/1/2017 2:32 PM32017611432042,887.61
July 31, 20164201673100042,582.00
12:30 PM518991230123000.52
4/11/2017 11:24:146201741111241442,836.48
4/11/20177201741100042,836.00
 818991230000 
19189912310001.00
0.2510189912306000.25
4300011201792200043,000.00
  • 1 A random date typed in using slashes.
  • 2 A random date typed in using dashes. Note that it is processed the same way as the date with slashes.
  • 3 Typed a random date in and added a time. Now notice the hours and minutes being extracted.
  • 4 Typed in a date but spelled out. This also works, but it won't work if you write the day as "31st" instead if 31.
  • 5 If you only type in a time, the "zero" date is 12/30/1899.
  • 6 Entered with the NOW function. This will change constantly in the linked Google Sheet.
  • 7 Entered with the TODAY function. This will change daily in the linked Google Sheet.
  • 8 A blank cell is December 30, 1899. Similar to tickmark 5.
  • 9 Typing a 1 increments the value in number 8 above by 1 day. In other words "1=12/31/1899". It is just a matter of how it is displayed which can be controlled by going to the Format menu and choosing Number.
  • 10 Just a decimal with no whole number increments the value by hours, minutes and seconds instead of days.
  • 11 To get near the present date, you need to start with 43,000 days away from 12/30/1899.

 Live examples in Sheets 

Go to this spreadsheet for the examples of the YEAR, MONTH, DAY, HOUR, MINUTE, and SECOND functions shown above that you can study and use anywhere you would like.