Windows Dev Center

DateTime.DaysInMonth Method

Returns the number of days in the specified month and year.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Public Shared Function DaysInMonth ( _
	year As Integer, _
	month As Integer _
) As Integer


Type: System.Int32
The year.
Type: System.Int32
The month (a number ranging from 1 to 12).

Return Value

Type: System.Int32
The number of days in month for the specified year.
For example, if month equals 2 for February, the return value is 28 or 29, depending on whether year is a leap year.


month is less than 1 or greater than 12.


year is less than 1 or greater than 9999.

The DaysInMonth method always interprets month and year as the month and year of the Gregorian calendar even if the Gregorian calendar is not the current culture's current calendar. To get the number of days in a specified month of a particular calendar, call that calendar's GetDaysInMonth method.

The following example demonstrates the DaysInMonth method.

Const July As Integer = 7
Const Feb As Integer = 2

' daysInJuly gets 31.
Dim daysInJuly As Integer = System.DateTime.DaysInMonth(2001, July)

' daysInFeb gets 28 because the year 1998 was not a leap year.
Dim daysInFeb As Integer = System.DateTime.DaysInMonth(1998, Feb)

' daysInFebLeap gets 29 because the year 1996 was a leap year.
Dim daysInFebLeap As Integer = System.DateTime.DaysInMonth(1996, Feb)

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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