Optimize Largest Contentful Paint | Articles | web.dev

Note that these time breakdowns are guidelines, not strict rules. If the LCP times on your pages are consistently within 2.5 seconds, then it doesn't really matter what the relative proportions are. But if you're spending a lot of unnecessary time in either of the "delay" portions, then it will be very difficult to constantly hit the 2.5 second target. A good way to think about the breakdown of LC

[kzms2]

Lighthouse6.0でも重要なLCPについての最適化について。めっちゃ詳しく書いてある

[efcl]

LCPはFirst Viewortのレンダリングで最も大きなコンテンツが表示されるまでの時間。 2.5秒以内が目標値。 レスポンスタイムの改善、レンダリングにかかるJSやCSSのブロックの削減、ファイルサイズの削減、クリティカルパスCSS