MetricsLCP
Largest Contentful Paint
The time until the largest visible element in the viewport (image, video or text block) has rendered.
- Good
- <= 2.5 s
- Needs work
- 2.5 to 4 s
- Poor
- > 4 s
Field data (75th percentile)
LCP is the loading Core Web Vital. It answers the question a visitor cares about most: when does the page look ready? The clock starts when navigation begins and stops when the biggest above-the-fold element paints.
Because the largest element is usually a hero image or headline, LCP is dominated by how fast the server responds and how quickly that one resource can be delivered and decoded.
What moves it
- Slow server response (high TTFB) delays everything downstream.
- Large or unoptimised hero images, or images without a priority hint.
- Render-blocking CSS and JavaScript in the document head.
- Client-side rendering that paints the main content late.
Related terms
- CWVCore Web VitalsGoogle's set of three field metrics for loading (LCP), interactivity (INP) and visual stability (CLS) of a page.
- INPInteraction to Next PaintHow long the page takes to visually respond after a user interacts, measured across the whole visit.
- CLSCumulative Layout ShiftA unitless score for how much visible content unexpectedly moves around while the page loads and runs.
- FCPFirst Contentful PaintThe moment the browser renders the first piece of content: text, an image or a canvas.
- TTFBTime to First ByteThe time from the start of navigation until the browser receives the first byte of the response.
- FIDFirst Input Delay (retired)The delay between a visitor's first interaction and the browser starting to process it. Replaced by INP.
- TBTTotal Blocking TimeThe total time the main thread was blocked by long tasks between first paint and interactivity, measured in the lab.
- SISpeed IndexA lab metric for how quickly the visible parts of a page fill in during load, based on video capture.
- TTITime to Interactive (legacy)A lab metric for when a page has rendered and can reliably respond to input quickly.
- Page LoadThe classic load event: everything on the initial page, including images and subresources, has finished loading.
- Route LoadThe loading time of an in-app navigation in a single-page app, where no full page reload happens.
- Long Tasks & LoAFAny piece of JavaScript that occupies the main thread for more than 50 ms, blocking the page from responding.
- Experience ScoreA single 0 to 10 number fastmon derives from LCP, INP, CLS, FCP, TTFB, load time and error rate.
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