What does the Free Schema Markup Checker check?
It checks json-ld discovery, schema type detection, parse errors, seo/geo fix suggestions and returns a shareable Themerella report with evidence and fixes.
Free Tool
Free Schema Markup Checker
Find JSON-LD structured data, parse schema types, catch invalid JSON-LD, and suggest next fixes.
What this tool checks
Run one URL scan and get a complete report.
- JSON-LD discovery
- Schema type detection
- Parse errors
- SEO/GEO fix suggestions
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: schema 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: schema checker · structured data checker · json ld 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 Free Schema Markup 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 schema 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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