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Free Core Web Vitals Checker

Check a page's real-user Core Web Vitals — LCP, INP and CLS at the 75th percentile — from Chrome field data, and see whether it passes Google's Core Web Vitals assessment. Free, no account.

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Run a real check above

Submit a public URL, domain, or keyword. Novaverb will show only the evidence this tool can actually retrieve or measure.

Evidence model

Know what the result proves

Each free check separates measured evidence from interpretation, and interpretation from the deeper work available in a connected workspace.

database

1. Source

Real-user field data from the Chrome User Experience report. The result identifies where its evidence came from.

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2. Boundary

This reads real-user field data collected over the trailing 28 days for pages with enough Chrome traffic. Low-traffic pages fall back to origin-level data or report no field data — this is not a lab test.

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3. Next action

Use the finding to verify a problem, then connect a workspace when you need history, monitoring, or site-wide analysis.

Core Web Vitals explained

Field data is how Google actually judges page experience

Core Web Vitals measure loading (LCP), interactivity (INP) and visual stability (CLS) from real Chrome users — not a lab simulation. Google uses this field data as a ranking signal, so the p75 value is what matters, not a one-off lab score.

The three thresholds

LCP — Largest Contentful Paint: Good ≤ 2.5 s, Poor > 4 s.
INP — Interaction to Next Paint: Good ≤ 200 ms, Poor > 500 ms. This replaced FID in 2024.
CLS — Cumulative Layout Shift: Good ≤ 0.10, Poor > 0.25.

URL vs origin data

Low-traffic URLs may not have their own field data. In that case this tool falls back to origin (whole-site) data, which is clearly labelled — it reflects the site overall, not that single page.

Get the right answer

What to submit — and what to avoid

The check is only as honest as its input. These examples keep you out of the two mistakes that produce a misleading result.

check_circleUse it like this

yourdomain.comAny address form works — a URL with real traffic has the richest field data. http or https, with or without www, a bare domain or a full path — we normalize it for you.

https://www.yourdomain.com/The origin or a popular page is ideal; we fall back origin-level if a URL has no sample.

cancelAvoid this

Reading 'no field data' as an errorA brand-new or low-traffic page simply has no Chrome UX Report sample, so we honestly say so instead of guessing.

Public methodology

Exactly how this result is produced

No opaque score. Every result comes from these steps — so you can trust it, reproduce it, and explain it to a client.

We normalize the address and read 75th-percentile real-user field data from the Chrome UX Report (CrUX).
We report LCP, INP and CLS against the official Core Web Vitals thresholds.
We fall back from URL-level to origin-level data and label which scope the numbers came from.

Built on public standards

The international standards this check applies

Novaverb measures your site against these published specifications — not an opaque score. Each card names the standard, the body that maintains it, and exactly how this tool applies it.

GoogleCore Web Vitals

web.dev Web Vitals

Reports LCP, INP and CLS against the official Core Web Vitals thresholds.

Read the specification open_in_new

GoogleCrUX

Chrome UX Report

Reads 75th-percentile real-user field data from the Chrome UX Report.

Read the specification open_in_new

GooglePage experience

Page experience in Search

Reflects the page-experience assessment Google uses as a signal.

Read the specification open_in_new

verifiedWe list a standard only where this tool genuinely reads or measures against it. Where a signal is outside a live check, the result says so instead of implying coverage.

Common questions

Core Web Vitals Checker FAQ

What does the Core Web Vitals Checker report?

It reports real-user LCP, INP and CLS at the 75th percentile from Chrome field data over the trailing 28 days, and whether the page passes Google's Core Web Vitals assessment.

What are good Core Web Vitals values?

A page is considered good when LCP is 2.5 seconds or less, INP is 200 milliseconds or less, and CLS is 0.10 or less, all measured at the 75th percentile of real users.

What do LCP, INP and CLS actually measure?

LCP, Largest Contentful Paint, measures loading speed. INP, Interaction to Next Paint, measures responsiveness to input. CLS, Cumulative Layout Shift, measures visual stability. Together they reflect real perceived page experience for users.

Why does my page show no Core Web Vitals data?

Field data needs enough real Chrome traffic. Low-traffic pages fall back to origin-level data or report none at all. No data means insufficient samples, not that the page performs badly.

What is the 75th percentile in Core Web Vitals?

It means 75 percent of real page visits were at least this fast or stable. Google uses the 75th percentile so the assessment reflects most users, not just the fastest or an average, experience.

What is the difference between field data and lab data?

Field data is measured from real users' devices and networks over time, as this checker reports. Lab data comes from a single controlled test. Field data reflects genuine experience; lab data is reproducible but simulated.

How do I improve my Largest Contentful Paint?

Serve the main image or text quickly by optimising and preloading the largest element, reducing server response time, trimming render-blocking resources, and using efficient caching so LCP falls to 2.5 seconds or less.

Does passing Core Web Vitals guarantee higher rankings?

No. Core Web Vitals are part of Google's page experience signals and help, but relevance and content quality matter more. Passing removes a disadvantage rather than guaranteeing a ranking boost on its own.

Why is INP replacing older responsiveness metrics important?

INP measures the latency of real user interactions across the whole visit, not just the first. A good INP of 200 milliseconds or less means the page reliably responds quickly whenever users tap or click.

Is this checker a lab speed test?

No. It reports real-user field data at the 75th percentile from Chrome over 28 days. For a controlled lab audit with reproducible opportunities, use a Lighthouse-based tool like the PageSpeed Checker instead.

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