JavaScript Versions

JavaScript Versions


JavaScript was invented by Brendan Eich in 1995, and became an ECMA standard in 1997.

ECMAScript is the official name of the language.

From 2015 ECMAScript is named by year (ECMAScript 2015).


ECMAScript Editions

Ver Official Name Description
1 ECMAScript 1 (1997) First Edition.
2 ECMAScript 2 (1998) Editorial changes only.
3 ECMAScript 3 (1999) Added Regular Expressions.
Added try/catch.
4 ECMAScript 4 Never released.
5 ECMAScript 5 (2009)

Read More: JS ES5
Added "strict mode".
Added JSON support.
Added String.trim().
Added Array.isArray().
Added Array Iteration Methods.
5.1 ECMAScript 5.1 (2011) Editorial changes.
6 ECMAScript 2015

Read More: JS ES6
Added let and const.
Added default parameter values.
Added Array.find().
Added Array.findIndex().
7 ECMAScript 2016 Added exponential operator (**).
Added Array.prototype.includes.
8 ECMAScript 2017 Added string padding.
Added new Object properties.
Added Async functions.
Added Shared Memory.
9 ECMAScript 2018 Added rest / spread properties.
Added Asynchronous iteration.
Added Promise.finally().
Additions to RegExp.

ECMAScript is often abbreviated to ES.


Browser Support

ECMAScript 3 is fully supported in all browsers.

ECMAScript 5 is fully supported in all modern browsers.


Browser Support for ES5 (2009)

Browser Version From Date
Chrome 23 Sep 2012
Firefox 21 Apr 2013
IE 9* Mar 2011
IE / Edge 10 Sep 2012
Safari 6 Jul 2012
Opera 15 Jul 2013

* Internet Explorer 9 does not support ECMAScript 5 "use strict".


Browser Support for ES6 (ECMAScript 2015)

Browser Version Date
Chrome 58 Apr 2017
Firefox 54 Jun 2017
Edge 14 Aug 2016
Safari 10 Sep 2016
Opera 55 Aug 2017

Internet Explorer does not support ECMAScript 2015.


Browser Support for ES7 (ECMAScript 2016)

Browser Version Date
Chrome 68 May 2018
Opera 47 Jul 2018


JavaScript / ECMAScript

JavaScript was developed for Netscape. Netscape 2 was the first browser to run JavaScript.

After Netscape the Mozilla foundation continued to develop JavaScript for the Firefox browser.

The latest JavaScript version was 1.8.5. (Identical to ECMAScript 5).

ECMAScript was developed by ECMA International after the organization adopted JavaScript.

The first edition of ECMAScript was released in 1997.

This list compares the version numbers of the different products:

Year JavaScript ECMA Browser
1996 1.0 Netscape 2
1997   ECMAScript 1 IE 4
1998 1.3   Netscape 4
1999   ECMAScript 2 IE 5
2000   ECMAScript 3 IE 5.5
2000 1.5   Netscape 6
2000 1.5   Firefox 1
2011   ECMAScript 5 IE 9 (Except "use strict")
2011 1.8.5 Firefox 4 (Except leading zeroes in parseInt)
2012   IE 10
2012     Chrome 23
2012     Safari 6
2013     Firefox 21
2013     Opera 15
2015   ECMAScript 2015 Partially Supported in all Browser

IE 4 was the first browser to support ECMAScript 1 (1997).

IE 5 was the first browser to support ECMAScript 2 (1999).

IE 5.5 was the first browser to support ECMAScript 3 (2000).

IE 9* was the first browser to support ECMAScript 5 (2011).

Internet Explorer 9 does not support ECMAScript 5 "use strict".

Chrome 23, IE 10, and Safari 6 were the first browsers to fully support ECMAScript 5:

Chrome 23 IE10 / Edge Firefox 21 Safari 6 Opera 15
Sep 2012 Sep 2012 Apr 2013 Jul 2012 Jul 2013