Core Web Vitals

In practice

Under the acronyms, the three vitals measure three things a visitor actually feels. LCP (Largest Contentful Paint) is how long until the main thing on the page shows up. INP (Interaction to Next Paint) is how quickly the page reacts when they tap or click. CLS (Cumulative Layout Shift) is how much the page jumps around while loading, the reason you tap the wrong button as an ad shoves everything down.

For industrial and B2B companies, the practical takeaway is simpler than the acronyms: buyers should see meaningful content in under three seconds. Most industrial sites we test are slower than that, so passing Core Web Vitals puts a site ahead of most of its peers before a word is read. Google publishes the exact thresholds for each metric ^[1].

Google measures these two ways, and the difference matters. "Lab" scores come from a single simulated load (what PageSpeed Insights shows on demand); "field" data is what real visitors experienced over the past month, which is what actually feeds ranking. A page can look fine in a lab test and still fail in the field on the mid-range phones your buyers use. The vitals are part of what Google calls page experience ^[2].

What moves them is usually unglamorous: oversized images, a heavy CMS theme, third-party scripts (chat widgets, analytics, embeds), and fonts that block rendering. None of them require a redesign to fix, which is why vitals are often the cheapest credibility win available, measurably faster and ahead of most peers, without touching the message.

You can check your own in two minutes: run your homepage through Google's PageSpeed Insights and read the top section, which reports real-user vitals as pass or fail. If it says your LCP is above 2.5 seconds, that's the number buyers feel, and the one worth fixing first.