LCP, CLS, and INP against Google's thresholds
The exact three metrics Google's ranking systems use to judge loading, stability, and responsiveness - checked against the official thresholds, honestly labeled as lab or field data.
Audit my Core Web VitalsThe official thresholds
| Metric | Good | Needs improvement | Poor |
|---|---|---|---|
| LCP Largest Contentful Paint | < 2.5s | 2.5s - 4s | > 4s |
| CLS Cumulative Layout Shift | < 0.1 | 0.1 - 0.25 | > 0.25 |
| INP Interaction to Next Paint | < 200ms | 200ms - 500ms | > 500ms |
Lab vs. field, stated plainly
LCP and CLS are measured directly in a controlled lab run - repeatable, available every time.
INP is field-only by nature. Total Blocking Time (TBT) stands in as the lab proxy; real INP data from actual visitors is shown alongside it when available.
Good
Needs work
Poor
Frequently asked questions
LCP (Largest Contentful Paint) measures loading speed, CLS (Cumulative Layout Shift) measures visual stability, and INP (Interaction to Next Paint) measures responsiveness to user input. Google uses all three as ranking signals.
INP is a field metric - it needs real user interactions over time, so it can only come from data about real visits. A lab audit like this one measures Total Blocking Time (TBT) as the closest lab proxy for interaction responsiveness. When real-visitor data exists for your site, we show its INP alongside the lab results.
Lab data is a single controlled audit run under fixed conditions - repeatable, but not necessarily representative of every real visitor. Field data is aggregated from real visitors who actually used your site, capturing the range of devices and networks they had. Both are useful; they answer different questions.
Core Web Vitals are one ranking signal among many, not a pass/fail gate. That said, poor scores - especially LCP and CLS - correlate with worse user experience regardless of ranking impact, so they're worth fixing on their own merits.
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Audit your Core Web Vitals
LCP, CLS, and INP against Google's thresholds, honestly labeled.
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