What is headless browser testing in Selenium?

Headless browser testing runs browser tests without displaying the browser window. The browser still renders pages and executes JavaScript — everything happens in the background.

Benefits:

• ✓Faster execution — no UI rendering overhead
• ✓Runs in CI/CD pipelines — no display server needed
• ✓Consumes less memory
• ✓Still supports screenshots and JavaScript execution

Chrome Headless:

ChromeOptions options = new ChromeOptions();
options.addArguments("--headless");
options.addArguments("--no-sandbox");
options.addArguments("--disable-dev-shm-usage");
options.addArguments("--window-size=1920,1080");

WebDriver driver = new ChromeDriver(options);
driver.get("https://automateqa.online");
System.out.println(driver.getTitle());

Firefox Headless:

FirefoxOptions options = new FirefoxOptions();
options.addArguments("--headless");
WebDriver driver = new FirefoxDriver(options);

Common use cases:

• ✓Jenkins, GitHub Actions, GitLab CI pipelines
• ✓Docker containers
• ✓Scheduled overnight regression runs

Note: Chrome 112+ uses --headless=new for better compatibility with modern web apps.