What Is The Difference Between Selenium 3 And Selenium 4?


Subscribe to our Newsletter

With the first website going LIVE on August 6, 1991, by British physicist Tim Berners-Lee in Switzerland, to an enormous array of over 1,169,621,187 LIVE websites on the internet, the vast domain of the digital world is incomprehensible.

What makes the sites successful and not drowned in a lot of 75% of websites today - which are not active but instead parked domains or similar - is the quality and valuable experience they bring to the table.

And to test the efficacy and effectiveness of the sites, Selenium has developed a comprehensive framework that is a complete suite of automated tools all under your fingertips. This article will discuss Selenium, its framework, and the significant difference between Selenium 3 and Selenium 4 - the latest stable testing software releases. So without any further ado, let's get started!

What is Selenium?

Selenium is a web testing tool commonly used to test web applications written in modern programming languages. Selenium is a popular technology for testing web applications, providing a means to automate the testing of web pages and forms. It is a cross-browser testing tool that enables interaction with all web browsers using a single test script.

Selenium's automated suite comes along with the following components:

1. Selenium Core

The Selenium core is the heart of the Selenium testing suite. It consists of a suite of client-side testing tools, including a browser simulator, test automation server, and Remote Control server. Currently, the Selenium core supports the most popular web browsers, including Google Chrome, Firefox, Internet Explorer, Safari, and JSON Wire Format.

2. Selenium RC

Selenium Remote Control (Selenium-RC) is a browser extension that allows you to navigate the web and perform tasks like browsing, starting new tabs, and searching the web. It is a valuable tool for automating the testing of a browser and detecting regressions in the browser as well as for other testing purposes.

3. Selenium IDE

Selenium IDE is a free editor for automating web applications. It allows users to record their actions, save them for later review, and replay them to ensure that their automated tests work as expected.

4. Selenium Grid

Selenium Grid is a tool that helps distribute the work across a group of machines to run tests across browsers and platforms. It can also manage the launch and termination of the shared instances.

5. Selenium Webdriver

The Selenium WebDriver is a browser-based API that allows users to interact with web pages. It provides a means for users to perform actions, such as clicking on a button, in the context of a web application. The Selenium WebDriver allows users to automate the testing of web applications on any platform, such as a web browser, headless browser, or mobile device. It supports all major web browsers and the JSON (JavaScript) Wire Format.

Selenium in the Market

Selenium has been a demanding tool in the market since its inception in 2008 when Selenium 1 was released. Since then, it has evolved into a robust and complete testing tool used by a wide range of developers to ensure the success of their web applications.

Selenium 3, or Selenium WebDriver, is the most commonly used Selenium framework to test web applications. Selenium 4, also known as SeleniumHub, is a framework that allows engineers to run tests using multiple browsers and Selenium frameworks from a single platform. Selenium 4 is equipped with the latest W3C WebDriver for enhanced testing capabilities.

Also Read: Leading Selenium Testing Service Provider

Selenium 3 Framework

The ultimate framework of selenium 3 includes JSON Wire protocol, which has now been replaced by W3C WebDriver protocol in the latest release.

JSON Wire is an interoperable application-level protocol for exchanging data between different Selenium-based browsers. It is one of the essential standards to ensure all web browsers can seamlessly interface with each other.

JSON stands for JavaScript Object Notation. It is used as the data exchange protocol between Selenium Grid Control Manager and the browser. The objective of the JSON Wire protocol is to enable interoperability amongst Browser Selenium Grid, then run the tests using multiple selenium grids, where one grid can communicate with other grids without worrying about the framework.

Selenium 4 Framework

Contrasting to the previous version, Selenium 4 has been designed to connect the client and server using the WebDriver.

Selenium 3 and Selenium 4 involve using W3C WebDriver, an organisation that develops and promotes web standards. This allows for a more reliable and efficient testing environment.

As far as their Selenium frameworks are concerned, Selenium 3 and Selenium 4 and the most popular frameworks. The latest release features crucial improvements in the areas of testing and performance. Let's move over to see how the newest Selenium is built differently:

difference between Selenium 3 and Selenium 4
difference between Selenium 3 and Selenium 4

Comparison Between Selenium 3 and Selenium 4

  • In selenium 4, the chrome driver class extends to chromium driver with a bunch of predefined functions to access the primary dev tool. On the other hand, Selenium 3 had the chrome driver growing directly to the remote web driver. This upgrade has dynamically improved the functionality of the Selenium tool.
  • Another notable advancement is the mode of communication between the test code and the browser. Selenium 4 now uses the WebDriver W3C as it has W3C compliance, while version 3 had JSON wire protocol as their principal mode of communication between the code and browser.
  • W3C web driver is a newer and better alternative to the older JSON wire protocol. W3C web driver is an open W3C standard that allows it to access the browser DOM with a simple WSDL-based web service and run tests using Selenium without needing to install any special browser plugins.
  • Testers using Selenium 3 had to start the node jars and the hub every time to perform automation tests on the grid. At the same time, the latest version skips this step and allows the automation much quicker by eliminating the startup.

Advantages of Selenium 4

1. Consistency

Selenium 4 is consistent in terms of the way it interacts with the browser. This is because the WebDriver has been designed to be compatible with the Selenium Grid. The introduction of W3C has made standards more critical in the Selenium Framework.

2. Improved Standards

The standards have been designed to make it easier for developers to create more reliable and efficient tests. Encoding and decoding of the requests have been eliminated since selenium 4 is W3C web driver compliant.

3. API enhancements

The latest Selenium features a robust API that allows easy management of Selenium Grid and multiple windows or tabs. This is useful in testing numerous browsers on a single machine or even a multi-threaded application.


Looking at the differences between Selenium 3 and 4, it can be concluded that the latest version is the most advanced among the two. The addition of the W3C WebDriver has made it much easier to create reliable and efficient tests.

Selenium 4 is a well-designed and feature-rich testing framework. It has simplified the process of setting up the automation framework and improved the performance of the tests. It has also made it easy to create reliable and efficient tests. With the recent release of Selenium 4, it has become one of the most popular frameworks in the industry.

Also Read: Selenium Framework: Know All About It

Contact Us

Hire vetted developers & testers with Appsierra to build & scale your software products

Trusted by 100x of startups and enterprise companies like

Subscribe to Our Newsletter