Measuring page load times is essential for enhancing user experience and maintaining competitive search engine rankings, as slow-loading websites lead to higher bounce rates and reduced conversions. Selenium, an automated testing framework, coupled with the Navigation Timing API, can effectively measure and optimize page load times across different browsers and platforms. The Navigation Timing API, accessible through the window.performance object, provides detailed metrics on various load events, allowing developers to identify performance bottlenecks. By utilizing Selenium for automated cross-browser testing, developers can efficiently gauge the page speed across numerous device and browser combinations, ensuring optimal performance and user satisfaction. Techniques like file compression, browser caching, and minimizing redirects are essential for improving load times, and tools like LambdaTest offer scalable solutions for conducting these tests in a cloud environment.