JavaScript Object prototype

Example

Use the prototype property to add a new property to all objects of a given type:

function employee(name, jobtitle, born) {
  this.name = name;
  this.jobtitle = jobtitle;
  this.born = born;
}
employee.prototype.salary = 2000;

const fred = new employee("Fred Flintstone", "Caveman", 1970);
Try it Yourself »

Description

The prototype is a global property available with all JavaScript objects.

The prototype property allows you to add new properties and methods to objects.


Syntax

object.prototype.name = value

Browser Support

prototype is an ECMAScript1 (ES1) feature.

ES1 (JavaScript 1997) is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes Yes

Copyright 1999-2023 by Refsnes Data. All Rights Reserved.