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Core Web Vitals Checker
Review available LCP, INP and CLS measurements from eligible Chrome samples for the HTTPS origin. This lookup does not certify individual pages or predict rankings.
Quick answer
What are Core Web Vitals?
Core Web Vitals describe loading, responsiveness and visual stability through LCP, INP and CLS. This checker uses available Chrome field data for the HTTPS origin. Origin-level results aggregate pages and eligible samples; they do not certify every page, device or visitor experience.
Understand the scope of the result
The tool reports available 75th-percentile values and complete performance distributions. It requires LCP, INP and CLS for its overall assessment; missing core evidence produces an incomplete result. FCP and TTFB are additional diagnostics, not Core Web Vitals.
Field data aggregates sampled experiences. A lab test investigates a particular page under chosen conditions. Use both kinds of evidence when diagnosing a problem.
Investigate the measured problem
- For LCP, inspect the actual largest element, its loading path and server response before choosing an optimization.
- For INP, profile interactions and long tasks before changing scripts or event handlers.
- For CLS, identify shifting elements and reserve appropriate space for images, embeds and dynamic content.
- Test changes on representative pages and devices, then review later field data.
Keep performance and search outcomes separate
Google uses Core Web Vitals in its ranking systems, but good scores do not guarantee top rankings. This lookup does not measure indexing, content relevance, conversion changes or AI citations.
Where this data comes from
The server queries the Chrome UX Report API for the HTTPS origin and caches successful records for up to one day. The API uses an aggregation window, so lookup time is not the measurement date; inspect the available collection end date. Invalid percentiles are omitted, and incomplete distributions remain unavailable. Device shares describe eligible Chrome samples. No laboratory run or individual-page certification is performed.
Frequently asked questions
What are good Core Web Vitals scores?
The tool uses good thresholds of LCP at most 2.5 seconds, INP at most 200 milliseconds and CLS at most 0.1, assessed at the 75th percentile. Its overall assessment requires all three metrics. An origin-level result does not prove every page or device meets those thresholds.
Why does my site show no Core Web Vitals data?
Eligibility, sample coverage and unavailable sources can limit field data. Missing evidence is not proof of poor performance or low traffic. Investigate specific pages with a lab test and review available field data separately.
Do Core Web Vitals affect Google rankings?
Google uses them in its ranking systems, but good scores do not guarantee a ranking or replace helpful, relevant content. Measure actual search performance separately from this origin-level lookup.
What’s the difference between this and PageSpeed Insights?
This checker requests origin-level Chrome field records. PageSpeed Insights can provide page-specific diagnostics and available field data. A laboratory result and an aggregated field result answer different questions and can differ.
What does INP measure?
INP measures responsiveness to interactions. Use interaction profiling to identify delays and check the scope of the field sample before treating one result as representative of every page.
How often does this data update?
The source aggregates experiences over time, and our successful records may be cached for up to one day. Inspect the collection end date. A deployed fix does not immediately replace all older experiences in an aggregate.
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