What does the Core Web Vitals Checker check?
It checks initial response time, html weight, script count, css count, image count, lazy-loading signals and returns a shareable Themerella report with evidence and fixes.
Free Tool
Core Web Vitals Checker
Start with fast performance signals now, then plug Lighthouse/PageSpeed data into the same report structure later.
What this tool checks
Run one URL scan and get a complete report.
- Initial response time
- HTML weight
- Script count
- CSS count
- Image count
- Lazy-loading signals
How it works
The scanner fetches the public page, follows a limited redirect chain, collects headers/resources/HTML, applies self-owned detection rules, checks SEO/security/accessibility/performance signals, and returns evidence-backed fixes.
Private IPs, localhost, file URLs, and internal hostnames are blocked to reduce SSRF and abuse risk.
Search intent
Built for the task behind: core web vitals checker
People searching this topic usually want to verify a real website, see proof, and decide what to fix next. The first screen stays focused on that task: enter a URL, run the scan, review evidence, then copy the fix list.
Keyword cluster: core web vitals checker · performance checker · lighthouse checker
Output
Evidence-backed website report
The report groups technology, SEO, security, accessibility, performance, redirect, robots, sitemap, and schema findings into a prioritized action list.
FAQ
Common questions
Is the Core Web Vitals Checker free?
Yes. The first workflow is free and URL-first: enter a public website URL, run the scan, and review the report before any paid monitoring or API layer.
How is this different from a generic core web vitals checker page?
Themerella shows evidence, confidence, issue severity, and developer-ready fixes instead of only listing detected logos or generic advice.
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