What is Largest Contentful Paint (LCP)?
Largest Contentful Paint (LCP) is a Core Web Vitals metric that measures how long it takes for the largest content element visible in the viewport, usually a hero image, heading or main block, to render after a page starts loading. It is Google's proxy for how quickly a page feels usefully loaded to a visitor. A good LCP is 2.5 seconds or less, measured on real-world field data rather than a lab test.
Largest Contentful Paint (LCP), explained properly.
What LCP actually measures
LCP records the moment the biggest, most important thing on screen finishes rendering, because that is roughly when a visitor perceives the page as loaded and useful. It is deliberately about the largest visible element, a hero image, a headline or a main text block, rather than the very first pixel, since a page that shows a spinner quickly but its real content slowly still feels slow. Google measures it on field data from real Chrome users, not just a synthetic lab run, so it reflects genuine connections and devices rather than an ideal test.
Why LCP matters
LCP is one of the three Core Web Vitals Google uses as a ranking signal, and it is the one buyers feel most directly: a slow-appearing hero is the difference between a visitor who stays and one who bounces before the page is usable. A poor LCP usually points to a real, fixable cause rather than bad luck, an oversized image, a slow server response, or a resource the browser is forced to wait on. Because it is measured on real users, it also cannot be gamed by a fast lab score while actual visitors wait.
How LCP is improved
Improving LCP is engineering, not a plugin. The common levers are right-sizing and modernising the largest image so it downloads fast, improving server response time so the page starts rendering sooner, removing render-blocking scripts and stylesheets from the critical path, and preloading the key resource so the browser fetches it early. The honest first step is diagnosis: LCP has a specific cause on each page, and fixing the wrong thing wastes effort. We trace it to its real cause and fix it at the source.
Largest Contentful Paint (LCP): common questions.
What is a good LCP score?
2.5 seconds or less is considered good, between 2.5 and 4 seconds needs improvement, and over 4 seconds is poor. The figure that matters is the real-user field data, not a one-off lab score.
What causes a slow LCP?
Most often an oversized or slow-loading hero image, a slow server response time, or render-blocking scripts and stylesheets that delay the largest element from appearing.
Does LCP affect SEO?
Yes. It is one of the three Core Web Vitals Google uses as a ranking signal, and slow pages also lose conversions, so it links engineering to both rankings and revenue.