CrUX

Chrome User Experience Report

The dataset provides information about real-world performance and user experience metrics for websites and web applications. Google maintains CrUX based on data collected from millions of Chrome browser users. The CrUX dataset includes various performance metrics:

• First Paint: The first key moment when the browser has started to render the page
• First Contentful Paint (FCP): The time it takes to display the first content on the screen.
• DOM Content Loaded: The time it takes for the initial HTML document to completely load, without stylesheets, images, or subframes to finish loading.
• Largest Contentful Paint (LCP): The time it takes to display the largest content element on the screen.
• Onload: When the pages and their dependent resources have finished loading.
• Cumulative Layout Shift (CLS): A metric that measures the visual stability of a page by quantifying unexpected layout shifts.
• First Input Delay (FID): a measurement of load responsiveness when the user is trying to interact with the page.
• Interaction to Next Paint (INP): the latency of all interactions throughout the entire page lifecycle.

These metrics, along with other experimental ones, provide insights into how users perceive the performance of a website or web application. They help website owners and developers understand and optimize the user experience, particularly with page load times and visual stability.

CrUX data is integrated into various tools and services developers use for performance analysis and optimization. One of the primary tools is the PageSpeed Insights tool, which provides a performance score and recommendations for improving web page speed and user experience. The data is also used in the Lighthouse auditing tool, which offers detailed performance metrics and suggestions for improving a website’s performance.

Web developers and site owners leverage CrUX data for benchmarking, monitoring, and making data-driven decisions regarding performance improvements. By analyzing CrUX data, developers can identify areas where their websites are underperforming and take targeted actions to enhance the user experience.

It’s worth noting that CrUX data is anonymized and aggregated to ensure user privacy. The dataset represents a broad range of users and provides insights into performance across different devices, network conditions, and regions.

• Abbreviation: CrUX
• Source: Chrome UX Report