How to Clone a Date Object in JavaScript

In this tutorial, we will show how you can clone or copy a Date instance. The following example clones the current date which becomes possible with the <kbd class="highlighted">getTime()</kbd> method of the Date object which returns the number of milliseconds since 1 January 1970 00:00:00 (epoch time):

Javascript clone a date object

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
  </head>
  <body>
    <script>
      let currentDate;
      currentDate = new Date();
      document.write(currentDate);
      let clonedDate = new Date(currentDate.getTime());
      document.write("<br />" + clonedDate);
    </script>
  </body>
</html>

Try it Yourself »

The <kbd class="highlighted"> valueOf()</kbd> method for Date objects performs the same result as the <kbd class="highlighted">getTime()</kbd> method (the number of milliseconds since epoch time) and returns the primitive value of a Date object.

Javascript clone a date object

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
  </head>
  <body>
    <script>
      let date = new Date()
      document.write(date);
      let copyOf = new Date(date.valueOf())
      document.write("<br />" + copyOf);
    </script>
  </body>
</html>

Try it Yourself »

The getTime() Method

The <kbd class="highlighted">Date.prototype.getTime()</kbd> method returns the number of milliseconds since the Unix Epoch. It uses UTC standard for the time representation. The method can be used to assign a date and time to another Date object. It is functionally equivalent to the <kbd class="highlighted"> valueOf()</kbd> method.