Core Web Vitals explained, in plain English.
LCP, INP, and CLS. These are the three numbers Google uses to rank your site on page experience. Here is what each one measures, what the targets are, and how to fix yours. INP replaced FID in March 2024.

Why Google invented Core Web Vitals.
Before Core Web Vitals, Google measured site speed with a single number, page load time which did not reflect how sites actually feel to visitors. CWV replaced that with three specific metrics that measure real user experience: how fast does the main content appear (LCP), how fast does the page respond to a tap (INP), and does the layout shift around while loading (CLS).
- LCP. Largest Contentful Paint, target under 2.5s
- INP. Interaction to Next Paint, target under 200ms (replaced FID)
- CLS. Cumulative Layout Shift, target under 0.1
The three metrics, explained.
How SchemaReports measures Core Web Vitals.
SchemaReports fetches your live page in a browser context and measures LCP, INP, and CLS the same way Chrome does for real users. Not simulated. Not cached. Real values on the live site. Every slow element is identified by selector. Phase 1 of every audit, free or paid.
- Live measurement, not simulation
- Element-level identification
- Specific fix recommendations

Core Web Vitals, common questions
Do Core Web Vitals actually affect rankings?
Yes, they are a confirmed Google ranking signal as part of the page experience update.
- Foundation phases cover Core Web Vitals, PageSpeed, meta tags, heading structure, and crawlability, the technical baseline that affects how search engines access and understand your site.
- Content, Trust, and Compliance phases cover content quality, E-E-A-T signals, conversion effectiveness, schema markup, local SEO, ADA accessibility, and AI readiness, over 1,000 distinct data points total.
What is a good score?
Under 2.5s LCP, under 200ms INP, under 0.1 CLS.
- Rule-based tools flag issues based on fixed criteria, missing meta descriptions, images without alt text. These checks are useful but they do not require understanding your content. Any tool can do them.
- Our AI reads your content semantically, it understands what your pages are about, who they are written for, and what is missing. That analysis produces recommendations unique to your business that you will not see in a templated report.
What happened to FID?
Retired in March 2024 and replaced by INP. INP is a better metric because it measures the entire page lifetime.
- All reports stay branded SchemaReports (gray label). Agencies get the GoHighLevel integration that auto-creates contacts with audit data in custom values, the value flows into your CRM, not a fake-branded PDF.
- Agency plan also includes an embeddable audit widget you can add to your own website, plus client seat management so clients can log in and view their reports directly without contacting you.
Why is TBT not a Core Web Vital?
TBT is a lab metric (measured during development). INP is a field metric (measured from real users). Google ranks on field metrics.
- Every audit can be downloaded as a formatted PDF for client presentations, as Markdown for documentation or CMS publishing, or as JSON for importing data into dashboards, CRMs, or custom tools.
- Agency plan users can also access reports programmatically via the full API, pull audit data into your reporting stack without manual downloads.
Can I use Lighthouse instead?
Lighthouse runs a lab version of the check. SchemaReports runs the live version. Both are useful, live is more accurate.
- All paid plans include a 30-day satisfaction guarantee. If you are not satisfied within the first 30 days, you receive a full refund, no questions, no contract obligations.
- Subscriptions can be cancelled at any time. There are no long-term contracts. Access continues through the end of your current billing period after cancellation.
- A public API is on the roadmap. Today every audit exports as PDF, Markdown, and JSON on every plan for manual integration.
- API documentation is available after account creation. Use it to run audits programmatically, retrieve structured results, and integrate SchemaReports data into your client reporting stack.
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