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IsLeapYear Method

DateTime.IsLeapYear Method

Returns an indication whether the specified year is a leap year.

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

public static bool IsLeapYear(
	int year


Type: System.Int32

A 4-digit year.

Return Value

Type: System.Boolean
true if year is a leap year; otherwise, false.


year is less than 1 or greater than 9999.

year is specified as a 4-digit base 10 number; for example, 1996.

year is always interpreted as a year in the Gregorian calendar. To determine whether a particular year was a leap year in some other calendar, call that calendar object's IsLeapYear method.

The following example uses the IsLeapYear method to determine which years between 1994 and 2014 are leap years. The example also illustrates the result when the AddYears method is used to add a year to a leap day.

using System;

public class IsLeapYear
   public static void Main()
      for (int year = 1994; year <= 2014; year++)
         if (DateTime.IsLeapYear(year))
            Console.WriteLine("{0} is a leap year.", year);
            DateTime leapDay = new DateTime(year, 2, 29);
            DateTime nextYear = leapDay.AddYears(1);
            Console.WriteLine("   One year from {0} is {1}.", 
// The example produces the following output: 
//       1996 is a leap year. 
//          One year from 2/29/1996 is 2/28/1997. 
//       2000 is a leap year. 
//          One year from 2/29/2000 is 2/28/2001. 
//       2004 is a leap year. 
//          One year from 2/29/2004 is 2/28/2005. 
//       2008 is a leap year. 
//          One year from 2/29/2008 is 2/28/2009. 
//       2012 is a leap year. 
//          One year from 2/29/2012 is 2/28/2013.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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