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Days in month

Excel formula: Days in month
Generic formula 
=DAY(EOMONTH(date,0))
Summary 

To get the number of days in a given month from a date, you can use a formula based on the EOMONTH and DAY functions.

In the example shown, the formula in cell B5 is:

=DAY(EOMONTH(B5,0))
Explanation 

The DAY function returns the day component of a date. The EOMONTH function returns the last day of the month for a given date. So, in this formula EOMONTH first returns a date corresponding to the last day of the month, and then DAY returns the date value for that date.

By definition, the value returned by DAY is always equal to the number of days in the month, since the date supplied to DAY is always the last day.

Author 
Dave Bruns
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Excel formula: Get last day of month
Get last day of month
The 2nd argument ( months ) of the EOMONTH function allows you to get the last day of the month in future or past months. When you use zero for months, EOMONTH will return the last day of the month in the same month. To get the last day of the prior...
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The Excel DAY function returns the day of the month as a number between 1 to 31 from a given date. You can use the DAY function to extract a day number from a date into a cell. You can also use the DAY function to extract and feed a day value...

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The Excel EOMONTH function returns the last day of the month, n months in the past or future. You can use EDATE to calculate expiration dates, due dates, and other dates that need to land on the last day of a month. Use a positive value for...

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