Web Performance Metrics Questions

Covers the key client side and front end performance metrics used to evaluate user experience and site responsiveness. Candidates should understand metrics such as First Contentful Paint, Largest Contentful Paint, First Input Delay, Cumulative Layout Shift, Time to Interactive, and Total Blocking Time; when each metric matters; and trade offs between them. Include knowledge of Google Core Web Vitals, how these metrics can influence search ranking and user engagement, and why performance should be treated as a business metric at senior levels. Expect familiarity with measurement approaches including lab testing tools and field measurement, for example Lighthouse, WebPageTest, and Real User Monitoring, plus instrumentation strategies for development and production. Be able to explain common optimization techniques and how they affect specific metrics, how to prioritize performance work, and methods for validating improvements and monitoring regressions in continuous delivery environments.