Find The Number Of Days For A Given Month With PHP

10th October 2008 - 1 minute read time

Note: This post is over a year old and so the information contained here might be out of date. If you do spot something please leave a comment and I will endeavour to correct.

There are two ways to find out the number of days for a given month. The first is to use the date() function in conjunction with the mktime() function to create a date and format this value as the number of days in a given month.

$monthDays = date("t",mktime(0, 0, 0, 12, 1, 2008));

The second way is to use the function cal_days_in_month(). This function takes three parameters.

Canelday: There are a number of different forms of calendar to chose from. The one most English speaking people are interested in is the CAL_GREGORIAN calendar. Take a look at a full list of calendar constants.
Month: An integer representing the month (1 - 12).
Year: An integer representing the year.

To find out the number of days in the month of December of 2008 you could use the following.

$monthDays = cal_days_in_month(CAL_GREGORIAN, 12, 2008);

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