[{"data":1,"prerenderedAt":62},["ShallowReactive",2],{"\u002Fglossary\u002Fspeed-index":3,"\u002Fglossary\u002Fspeed-index:related":45},{"id":4,"title":5,"author":6,"authorImage":7,"body":8,"category":30,"date":31,"description":32,"draft":33,"extension":34,"letter":35,"meta":36,"navigation":37,"path":38,"readTime":39,"related":40,"seo":41,"stem":43,"term":5,"__hash__":44},"glossary\u002Fglossary\u002Fspeed-index.md","Speed Index","Fabian Krumbholz","\u002Fimages\u002Fauthors\u002Ffabian-krumbholz.webp",{"type":9,"value":10,"toc":26},"minimark",[11],[12,13,14,17,18,21,22,25],"p",{},[15,16,5],"strong",{}," is a lab-based performance metric that measures how quickly the visual content of a page is populated during the page load. A lower score is better, as it indicates that the majority of the content in the visible viewport was rendered quickly. It is a key metric reported by tools like ",[15,19,20],{},"Lighthouse"," and ",[15,23,24],{},"WebPageTest"," to capture the perceptual speed of the loading experience.",{"title":27,"searchDepth":28,"depth":28,"links":29},"",2,[],null,"April 8, 2026","Speed Index is a lab-based performance metric that measures how quickly the visual content of a page is populated during the page load.",false,"md","S",{},true,"\u002Fglossary\u002Fspeed-index","1 min read",[],{"title":42,"description":32},"Speed Index: Definition | Web Performance Glossary","glossary\u002Fspeed-index","IBDloeBB2I3Hn98ZVB4j8B1nrVsj7MenhdsEb7FeSVE",[46,50,54,58],{"path":47,"title":48,"description":49,"letter":35},"\u002Fglossary\u002Fsearch-engine-optimization-seo","Search Engine Optimization (SEO)","SEO is the process of improving a website's visibility in search engine results pages (like Google). The goal is to rank higher than competitors for relevant search queries to attract more organic (free) traffic.",{"path":51,"title":52,"description":53,"letter":35},"\u002Fglossary\u002Fserver-response-time","Server Response Time","Server Response Time is a component of Time to First Byte that measures how long the server takes to process a request and start sending back a response, excluding network latency.",{"path":55,"title":56,"description":57,"letter":35},"\u002Fglossary\u002Fserver-timing","Server Timing","Server Timing is a browser API that allows the backend to communicate performance metrics about its own internal processes (e.g., database query time, time to render a component) to the browser via HTTP headers.",{"path":59,"title":60,"description":61,"letter":35},"\u002Fglossary\u002Fserver-side-ab-testing","Server-Side A\u002FB Testing","This is a performance-friendly method for running A\u002FB tests. Unlike Client-Side A\u002FB Testing, the decision of which variation to show a user is made on the Origin Server.",1787756716221]