Playwright vs Selenium: Which to choose in 2024

Test Automation Frameworks are vital in automated testing Websites. Playwright and Selenium are among the most popular test automation frameworks.

While Playwright is a newer Framework, Selenium is a legacy Library which has been supporting browser automation. Playwright supports Chromium, Firefox, and WebKit browsers, while Selenium offers a wide variety of browser support with Chrome, Firefox, IE, Edge, Opera, and Safari making it ideal for Cross Browser Testing.

This article covers Playwright vs Selenium in detail to help you choose the most appropriate framework for your website test automation.

What is Playwright?

Playwright by Microsoft is the newest addition to the Headless Browser Testing frameworks in popular use. Built by the same team that created Puppeteer (Headless Browser Testing Framework for Google Chrome), Playwright is an open-source NodeJS-based framework.

• However, it provides wider coverage for cross-browser testing by supporting Chrome, Firefox, and WebKit, while Puppeteer only supports Chrome and Chromium browsers.
• Playwright is compatible with Windows, Linux, and macOS, and can be integrated with major CI/CD servers such as Jenkins, CircleCI, Azure Pipeline, TravisCI, etc. in addition to the testing frameworks like Jest, Jasmine, Mocha.
• Besides JavaScript, Playwright also supports multiple programming languages such as Python, Java, and .NET C#, giving more options to QAs writing test scripts.
• It is highly useful for cross-browser testing on complex applications due to its wide coverage, accuracy, and high speed. It offers end-to-end testing through its high-level API, allowing the tester to control headless browsers.

When the tester runs a Playwright test script, the UI is readied at the backend before the test interacts with web elements. While testers have to write code for the wait explicitly for other frameworks, Playwright ensures auto wait, making it easier to write concise test scripts. It also provides flexible testing through its capabilities, which cover a wide range of complex scenarios for comprehensive testing.

• The auto-wait feature in Playwright performs all relevant checks for an element, and the requested action is performed only when the checks are duly passed. This ensures that the parts perform as expected and the test results are more accurate. 
• Some actionability checks performed by Playwright include Attached, Visible, Stable, Receive Events, and Enabled.
• Playwright also supports the execution of simultaneous tests (AKA parallel testing) through Browser Context. This scales up testing and comes in handy when multiple web pages must be tested simultaneously.

Here one browser instance is used to create multiple, concurrent and isolated browser contexts, which can be closed when not needed. Each of these browser contexts could host multiple web pages simultaneously. Thus, scaling up when the volume is high and reducing it when not required ensures optimal usage of resources.

How to run Playwright tests

While Playwright launches browsers in the headless mode by default, it can also run the browsers in headful mode. By passing a flag, when the browser is launched, Playwright can be used to run browsers in headful mode for tests.

The following code can be used to launch a headful browser:

const { chromium } = require('playwright'); 

//to launch the headful browser for firefox and webkit, replace chromium by firefox and webkit

const browser = await chromium.launch({ headless: false });

For Linux systems, xvfb is essential for launching headful browsers. Since xvfb is pre-installed in Docker Image and Github Action, running xvfb before the Node.js command allows the browsers to run in the headful mode.

xvfb-run node index.js

What is Selenium?

Selenium is an open-source automation testing suite that is widely used for the automation testing of web applications. It automates browsers and interacts with UI elements to replicate user actions to test whether a web application is functioning as expected.

Through its single interface, the Selenium framework allows the tester to write test scripts in different languages such as Java, Ruby, Perl, C#, NodeJS, Python, and PHP, offering flexibility.

• Selenium supports a wide range of browsers and their different versions to enable cross browser testing of web applications.
• It is the most popular framework to test websites and ensure seamless and consistent user experiences across different browser and device combinations. 
• That is why Selenium is one of the most trusted automated testing suites in the software industry.

How to run Selenium Tests

Selenium launches browsers in headed mode by default, you can also launch the browser in headless mode by passing the arguments to chromeoptions().

Example to launch browser in headed mode

WebDriver driver = new ChromeDriver(options);
driver.get("https://www.bstackdemo.com/")

Example to launch browser in headless mode

ChromeOptions options = new ChromeOptions();

options.addArguments("--headless=new");
WebDriver driver = new ChromeDriver(options);
driver.get("https://www.bstackdemo.com/");

As we can see first we initialize an object of ChromeOptions() and then add the argument “–headless=new” which is then passed to ChromeDriver.

Playwright vs Selenium Comparison

Playwright vs Selenium: Which to choose?

Both Playwright and Selenium have advantages and limitations, which means choosing between them is subjective to the scenario they will be used for. It depends on the project requirements and the priorities to choose one among these two testing frameworks.

When to Use Selenium

1. Wide Browser Compatibility: Selenium supports various browsers like Chrome, Firefox, Safari, Internet Explorer, Edge, and Opera. It is ideal for testing across multiple browsers, including older versions.
2. Established and Mature Projects: Selenium is a well-established tool with a large community, extensive documentation, and numerous integrations. It is suitable for projects that need stability and extensive support.
3. Language Flexibility: Selenium supports multiple programming languages such as Java, C#, Python, Ruby, and JavaScript. It is useful if your team has expertise in a specific language or needs to integrate tests into an existing project using a specific language.
4. Existing Selenium Infrastructure: If your project already has a Selenium test suite and infrastructure, it may be more practical to continue using Selenium rather than switching to a new tool.

When to Use Playwright

1. Testing Modern Web Applications: Playwright is designed to test modern web apps, supporting all modern rendering engines (Chromium, WebKit, and Firefox). It handles complex scenarios involving multiple tabs, frames, and web workers efficiently.
2. Trace Viewer: Playwright Trace Viewer is a GUI tool that helps you explore recorded Playwright traces after the script has run. Traces are a great way for debugging your tests when they fail on CI. You can open traces locally or in your browser on trace.playwright.dev.
3. Headless Browser Testing: Playwright has built-in support for headless browser testing, which is often faster and more efficient for CI/CD pipelines. While Selenium also supports headless mode, Playwright’s implementation is more streamlined.
4. Handling Complex Interactions: Playwright offers advanced features such as automatic waiting, network interception, and support for multiple pages/tabs, making it easier to write tests for complex user interactions.
5. Consistent API Across Browsers: Playwright’s API is consistent across all supported browsers, which simplifies cross-browser testing and maintenance.
6. Parallel Test Execution: Playwright supports running tests concurrently across multiple browsers and contexts, making it faster and more efficient for large test suites unless like Selenium where we need to set up Selenium Grid to run the tests in parallel.

Talk to an Expert

Why Run Selenium or Playwright Tests on Real Devices

Here’s why you should run Selenium or Playwright Tests on Real Devices using BrowserStack Automate:

• Diverse Environment Testing: It enables the execution of Selenium or Playwright tests across a broad selection of browsers and operating systems, eliminating the necessity for maintaining local testing infrastructure. This ensures consistent application performance across various platforms.
• Concurrent Test Execution: By allowing simultaneous execution of multiple Selenium or Playwright test suites, BrowserStack Automate significantly cuts down on total testing time, facilitating quicker iterative feedback and accelerated deployment cycles.
• CI/CD Integration: The platform seamlessly integrates with major continuous integration and delivery systems, including Jenkins, Travis CI, CircleCI, and GitHub Actions, automating the testing process within the development pipeline.
• Diagnostic Tools for better debugging: BrowserStack provides comprehensive diagnostic capabilities, including detailed logs, screenshots, and video recordings of test sessions, aiding in the swift identification and resolution of issues.
• Testing on Real Devices: Beyond simulated environments, BrowserStack also supports testing on real devices and browsers on the cloud, offering more precise and real-world test outcomes.
• Customizable Test Execution: Users can tailor test executions to meet specific needs through BrowserStack’s user interface or APIs, enabling adaptable and controlled test runs.

Closing Notes

No matter which test automation framework is chosen, cross browser testing is mandatory. It is the only way to guarantee that the website delivers seamless and consistent UX, irrespective of the device and browser used to access them.

• However, Emulators and simulators simply do not offer the real user conditions for testing software. 
• Consider testing websites and apps on a real device cloud, preferably one that offers the latest devices, browsers, and OS versions. 
• This applies to both manual testing and automation testing.
  BrowserStack’s real device cloud provides 3000+ real browsers and devices for an instant, on-demand testing.
• It also provides a cloud Selenium grid for automated testing, which can be accelerated by 10X with parallel testing. 
• The cloud also provides integrations with popular CI/CD tools such as Jira, Jenkins, TeamCity, Travis CI, and more.
• Additionally, in-built debugging tools let testers identify and resolve bugs immediately.

Try Automation Testing on Cloud