Add days to a date in JavaScript

In this short article, we will show you how to add days to a date in JavaScript. Here, we will add the number of days to the given date using JavaScript.

We can also use the third party library such as Moment.js to manage the date object. You may also check the following articles.

• Get yesterday’s, today’s, and tomorrow’s date using JavaScript
• Convert a 12 hour format to 24 hour format using JavaScript
• Calculate age in years using JavaScript
• Time from now using Moment JS

Function

Let’s use the following function to add the number of days to a date using JavaScript.

function addDaysToDate(date, days) {
  var dt = new Date(date);
  dt.setDate(dt.getDate() + days);
  return dt;
}

var currentDate = new Date(); // currentDate.toLocaleDateString() - 2/4/2021
addDaysToDate(currentDate, 2).toLocaleDateString(); // 2/6/2021

var dt1 = new Date('09/02/2021'); // dt1.toLocaleDateString() - 9/2/2021
addDaysToDate(dt1, 5).toLocaleDateString(); // 9/7/2021

Create prototype

With the help of the same function above, we can easily create a prototype for a date for easy access.

Date.prototype.addDays = function(days) {
  var dt = new Date(this.valueOf());
  dt.setDate(dt.getDate() + days);
  return dt;
};

var currentDate = new Date(); // currentDate.toLocaleDateString() - 2/4/2021
currentDate.addDays(2).toLocaleDateString(); // 2/6/2021

var dt1 = new Date("09/02/2021"); // dt1.toLocaleDateString() - 9/2/2021
dt1.addDays(5).toLocaleDateString(); // 9/7/2021

That’s it for today.
Thank you for reading. Happy Coding..!! 🙂