Puppeteer VS Selenium

7 min readJan 8, 2025

Introduction

The development of reliable, efficient, and user-friendly applications has come to rely on the automated testing paradigm. Unlike in manual testing, when a human checks to see if an application works the way it should, in automated testing, “bots” do the checking with stunning speed and accuracy. This increased checking speed, however, does not come at the expense of developer time. Indeed, in the worst case, automated testing is a time-neutral activity for the software development lifecycle. Moreover, in the best case, it is a timesaving and a user-experience-saving activity in the life of a software application.

What is Puppeteer?

Developed by Google, Puppeteer is a Node.js library that interacts with the Chrome and Chromium browsers to perform automated tasks. Using the Chrome DevTools Protocol, it instructs the browser to do things like navigate to different URLs, capture full-page screenshots, and interact with web elements as if a real human were doing it. While there are many ways to automate web tasks, Puppeteer is particularly good at “headless” (i.e., non-GUI) testing. This means you can “run” a series of instructions through the browser without needing to see what it is doing. Moreover, that can make things faster and more resource-efficient.

Key Features of Puppeteer:

Headless and Headed Modes: You can run Puppeteer in both GUI and non-GUI (headless) modes.
High-Level API: Puppeteer gives you plenty of ways to command the browser lug around your test suite.
Automatic Browser Management: No more installing browsers, and no more compatibility issues. Puppeteer just works.
Direct Access to DevTools: Puppeteer lets you use the Chrome DevTools Protocol. So you have developer tools at your disposal when you’re writing tests.

The primary aim of Puppeteer is to support the web browser testing and quality assurance for Google Chrome and Chromium. While there are experimental adaptations to support Firefox, Puppeteer covers web browser testing for Chrome and Chromium comprehensively. Thus, if your web application serves primarily an audience that uses either of those two browsers, then Puppeteer stands out as an efficient and effectual tool for testing against your audience’s browser.

Some common use cases where Puppeteer excels are:

UI testing: Automated testing of UI components to ensure consistent user experiences.
Performance monitoring: Measuring page load times, monitoring network requests, and profiling CPU usage.
Web scraping: Efficient extraction of data from websites, including dynamic content, thanks to its ability to handle JavaScript, and
PDF Generation and Screenshots: Converting web pages to PDFs or taking screenshots of web pages. The Puppeteer does the automated user interface testing of that project in the cloud.

Sample Puppeteer Code Block for Capturing a Screenshot:

javascript

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const puppeteer = require(‘puppeteer’);

(async () => {

const browser = await puppeteer.launch();

const page = await browser.newPage();

await page.goto(‘https://example.com');

await page.screenshot({ path: ‘example.png’ });

await browser.close();

})();

This script initializes Puppeteer, navigates to a specified URL, takes a screenshot, and saves it as “example.png”.

What is Selenium?

Selenium remains the most popular tool for automated web app testing. It is particularly effective for cross-browser testing. Selenium provides numerous ways to interact with a web application. The most commonly used is the Selenium WebDriver, which gives commands for how the web browser should behave. The commands sent to the WebDriver are usually in the language of the programming browser chosen for testing (Java, C#, Ruby, etc.). The other tool is Selenium Grid, which supports parallel test execution across multiple browsers and devices.

Sample Selenium Code Block for Opening a Browser in Python:

python

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from selenium import webdriver

driver = webdriver.Chrome()

driver.get(‘https://example.com')

print(driver.title)

driver.quit()

This Python script uses Selenium to open Chrome, navigate to a URL, and print the page title.

Puppeteer vs Selenium: Head-to-Head Comparison

Performance

Puppeteer and Selenium are two commonly used browser automation tools. While they have several similarities, they also have many key differences. One of the most notable differences is that Puppeteer works best with Chrome as it is built on the Chrome DevTools Protocol. Selenium, on the other hand, is a multi-browser solution and therefore can be a bit slower, especially when switching between different browsers.

Browsers Support

Puppeteer works only with Chrome and Chromium and has limited support for Firefox. This makes Puppeteer perfect for those who want to work with a Chrome-only application. Selenium works with all major browsers, so it is a safe choice for those who want to test an application cross-browser.

Language Support

Puppeteer provides support solely for JavaScript and Node.js, but Selenium has a much broader range of language support. This enables Selenium to accommodate varied development teams that may prefer writing tests in languages other than JavaScript, such as Java, C#, Python, or Ruby.

Automation Attributes:

Headless Functionality: Both frameworks possess headless capabilities, but for sheer stability, you simply cannot beat Puppeteer’s integration with Chrome DevTools.
Parallel Testing: For large-scale projects, parallel testing is necessary, and Selenium Grid is a superb vehicle for that.
Mobile Testing: While Puppeteer does not natively support mobile browsers, Selenium, via Appium, provides a mobile testing solution.

Pros and Cons

Puppeteer:

Pros:

Executes quickly with Chrome.
Almost no setup involved; just download Chrome.
The API is clean and designed for common use cases.

Cons:

Only test with Chrome and Chromium, thus no cross-browser testing.
Only use JavaScript, which may not be great for teams that work in other languages.

Selenium:

Pros:

Runs on all major browsers, so has good cross-browser compatibility.
Supports almost any programming language, so works in any environment.
Has a huge user community, so help is easy to find.

Cons:

More to install and configure, so definitely not “test in the morning, test at night” friendly.
Can be slow, though that is more of a criticism of the API than of any specific implementation.

When to Choose Puppeteer?

Puppeteer is ideal for projects that:

Projects that primarily target users of Chrome or Chromium.
Puppeteer is also the best option for quick, Chrome-specific automation or UI testing.
If for some reason, your UI testing requires not just one but several instances of the browser, Puppeteer can handle that as well.
Because of how Puppeteer and the library it utilizes, Chrome DevTools Protocol, are configured, the tool is also well suited for anything that requires using Chrome’s built-in developer tools to perform tasks like profiling the browser’s performance or tracking down memory leaks.

When to Choose Selenium?

Selenium is best suited for software testing projects that demand:

Comprehensive testing across a multitude of web browsers and platforms.
Diverse teams that prefer different programming languages.
Complicated test setups, including parallel test execution and mobile device testing.
Infrequent but necessary changes to a stable testing framework.

Real-World Use Cases

Below are a few practical applications for Puppeteer and Selenium.

Puppeteer Use Cases:

Puppeteer is a great tool for testing the UI on a Chrome-based environment.
Because it works so closely with the rendering engine of Chrome, it can be very effective for web scraping, particularly on pages that use JavaScript to render their content.
It also has built-in functions to make taking screenshots and generating PDFs a very straightforward process.

Selenium Use Cases:

Selenium offers a few great options for testing web applications across multiple environments.
It is capable of doing some very impressive e-commerce and multi-step user-journey regression tests.
It can also straightforwardly test web applications across different browsers, and, using a headless version of either Chrome or Firefox, across different operating systems and devices.

Testsigma: A Modern Alternative

Though Puppeteer and Selenium are widely regarded as the most popular web automation testing tools, Testsigma shines as a modern alternative that reduces the overall complexity of the web automation testing process. Available in the cloud and powered by artificial intelligence, the web automation testing tool allows teams to create, manage, and run automated tests across a variety of platforms, including web and mobile apps, APIs, and more — with very little required coding effort.

Testsigma’s Primary Characteristics:

Multiple tools in one: With Testsigma, its like using multiple tools in one, as you can automate for web, mobile, desktop applications as well as APIs, all from the same place.
Accessible Interface: Testsigma provides a natural language-based test creation environment that is user-friendly for both technical and non-technical team members. Testsigma’s interface is a perfect medium for moving from test case creation to automation in a testing project.
Rather Far Reaching: Testsigma is quite comprehensive in that it supports testing on all major devices and browsers, ensuring that the tested software is compatible across platforms.
Ready-to-Go: Part of the cloud-based promise is that there’s no setup required, so you can start parallel testing without the worry of getting local infrastructure ready.

What makes Testsigma worthy of consideration?

It is especially advantageous for teams that wish to:

Minimize the intricate job of establishing and upholding test environments.
Facilitate cooperation among developers, QA engineers, and business analysts.
Propel their test automation endeavors forward without considerable upfront costs.

Eyes are on Testsigma because it makes sense: Organizations can now pay more attention to cranking out quality software and less to managing traditional test automation frameworks.

Conclusion

Powerful as they are, Puppeteer and Selenium serve distinct purposes in the world of web automation testing. Because it’s closely tied to the Chrome browser, Puppeteer is better for testing that needs to happen in Chrome alone, and for projects that require a quick setup and to be “governed by” (scene setting, really) the Chrome DevTools. Puppeteer is also a good choice for testing web apps that only need to pass the most basic checks for cross-browser compatibility. Selenium, on the other hand, is better for large-scale projects that need to test in multiple browsers, and for setups that require “advanced” or “intensive” testing configurations.

Testsigma, is a good choice, if you are looking for a tool that saves your time in setup, authoring as well as test execution and lets you automate for web, mobile, desktop as well as APIs — all from the same place.