How to get the number of days in a specified month using JavaScript ?

30 May, 2019
Given a month and the task is to determine the number of days of that month using JavaScript.
JavaScript getDate() Method: This method returns the number of days in a month (from 1 to 31) for the defined date.Syntax:Date.getDate()Return value: It returns a number, from 1 to 31, representing the day of the month.
Syntax:
Date.getDate()
Return value: It returns a number, from 1 to 31, representing the day of the month.
JavaScript getFullYear() Method: This method returns the year (four digits for dates between year 1000 and 9999) of the defined date.Syntax:Date.getFullYear()Return value: It returns a number, representing the year of the defined date
Syntax:
Date.getFullYear()
Return value: It returns a number, representing the year of the defined date
JavaScript getMonth() Method: This method returns the month (from 0 to 11) for the defined date, based on to local time.Syntax:Date.getMonth()Return value: It returns a number, from 0 to 11, representing the month.
Syntax:
Date.getMonth()
Return value: It returns a number, from 0 to 11, representing the month.
Example 1: This example gets the days in the month (february) of the year (2020) by passing the month (1-12) and year to the function daysInMonth.
<!DOCTYPE HTML> <html>     <head>         <title>             Get number of days in            a specified month        </title>         </head>           <body style = "text-align:center;">                   <h1 style = "color:green;" >             GeeksForGeeks         </h1>                  <p id = "GFG_UP" style =            "font-size: 15px; font-weight: bold;">        </p>                  <button onclick = "GFG_Fun()">            click here        </button>                  <p id = "GFG_DOWN" style =            "color:green; font-size: 20px; font-weight: bold;">        </p>                  <script>            var up = document.getElementById('GFG_UP');                          up.innerHTML = "Click on button to get the"                + " number of days in specified month";                              var down = document.getElementById('GFG_DOWN');                           function daysInMonth (month, year) {                return new Date(year, month, 0).getDate();            }                          function GFG_Fun() {                var date = new Date();                var month = 2;                var year = 2020;                down.innerHTML = "Number of days in " + month                             + "nd month of the year " + year                             +" is "+ daysInMonth(month, year);            }        </script>     </body> </html>                    
Output:
Before clicking on the button:
After clicking on the button:
Example 2: This example gets the days in the current month of the current year by passing the month (1-12) and year to the function daysInMonth.
<!DOCTYPE HTML> <html>     <head>         <title>             Get number of days in a specified month        </title>         </head>           <body style = "text-align:center;">               <h1 style = "color:green;" >             GeeksForGeeks         </h1>                  <p id = "GFG_UP" style =             "font-size: 15px; font-weight: bold;">        </p>                  <button onclick = "GFG_Fun()">            click here        </button>                  <p id = "GFG_DOWN" style =             "color:green; font-size: 20px; font-weight: bold;">        </p>                  <script>            var up = document.getElementById('GFG_UP');                          up.innerHTML = "Click on button to get the number"                    + " of days in specified month";                          var down = document.getElementById('GFG_DOWN');                           function daysInMonth (month, year) {                return new Date(year, month, 0).getDate();            }                          function GFG_Fun() {                var date = new Date();                var month = date.getMonth() + 1;                var year = date.getFullYear();                down.innerHTML = "Number of days in " + month                            + "th month of the year " + year                             +" is "+ daysInMonth(month, year);            }        </script>     </body> </html>                    
Output:
Before clicking on the button:
After clicking on the button:
javascript-date
JavaScript
Web Technologies
Web technologies Questions
Writing code in comment?
Please use ide.geeksforgeeks.org,
generate link and share the link here.
Difference between var, let and const keywords in JavaScript
Differences between Functional Components and Class Components in React
Remove elements from a JavaScript Array
Roadmap to Learn JavaScript For Beginners
Difference Between PUT and PATCH Request
Installation of Node.js on Linux
Top 10 Projects For Beginners To Practice HTML and CSS Skills
Difference between var, let and const keywords in JavaScript
How to insert spaces/tabs in text using HTML/CSS?
How to fetch data from an API in ReactJS ?