Measurement
Lighthouse
Google Lighthouse is an open-source, automated tool developed by Google for auditing web pages across five categories: Performance, Accessibility, Best Practices, SEO, and Progressive Web App (PWA). It is built into Chrome DevTools and available as a CLI, Node module, and via Google PageSpeed Insights.
Lighthouse generates lab-based performance scores (0–100) and provides prioritized recommendations. Key SEO-relevant metrics include First Contentful Paint, Largest Contentful Paint, Total Blocking Time, Cumulative Layout Shift, and Time to Interactive. Google Search Console's Core Web Vitals report reflects real-world data complementing Lighthouse's lab data.
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Related Terms
Measurement
FCP (First Contentful Paint)
Refers to the point at which the first pixel renders on a screen after a user navigates to a web page.
Measurement
FID (First Input Delay)
Refers to the metric that represents how quickly a response is given when an action is requested after the page is loaded.
Measurement
PageSpeed Insights
A Google tool that provides information about page opening speeds and user experience metrics.
Measurement
TTFB (Time to First Byte)
Refers to the time between the browser requesting a page and when it receives the first byte of information from the server.