What are the specific benefits of JavaScript code splitting for user experience and SEO?

When a webpage needs to load a large amount of JavaScript resources, code splitting can significantly improve user experience and indirectly enhance SEO performance by dividing the code into on-demand loading chunks. The specific benefits to user experience include: reducing the volume of initial loading resources, shortening the first screen loading time, and avoiding page卡顿 caused by large file loading; reducing the risk of main thread blocking by loading non-critical code (such as non-first-screen components or routes) on demand, thereby improving interaction response speed; and reducing unnecessary traffic consumption, which is especially suitable for mobile users with poor network conditions. The positive impact on SEO is reflected in: optimizing Core Web Vitals metrics (such as Largest Contentful Paint LCP, First Input Delay FID), meeting search engines' evaluation standards for page performance, and indirectly improving search rankings; reducing server load, ensuring that search engine crawlers can more efficiently crawl and index key content, and reducing crawling failures caused by resource loading timeouts. When implementing code splitting, it is recommended to prioritize splitting route-level or large component code and combine it with lazy loading technology, which is particularly practical for improving mobile user experience and search engine crawling efficiency.