StructuredValidator vs VitalSentinel Schema Validator

StructuredValidator is a free web tool for checking structured markup, with validation focused on JSON-LD. Paste JSON-LD or HTML to see results as you type. It detects Microdata and RDFa in pasted HTML, but validates JSON-LD only. Checks cover JSON syntax, contexts, types, property names, value formats, @id references, and required or recommended properties for supported rich-result features. The URL tool fetches public HTTP or HTTPS pages, extracts JSON-LD from server HTML, and validates it in the browser without rendering JavaScript. Fetches allow four redirects, eight seconds, 2 MB per page, and 12 requests per minute per visitor. A comparison view places two schema implementations side by side to show differences, missing properties, and coverage. Rich-result preview and API access are available. Validation history and preferences stay in browser storage, and the service says it does not retain validation data on its servers. Optional AI suggestions send markup and errors to an AI provider under that provider’s retention policy.

VitalSentinel Schema Validator checks structured data on a page URL and separates missing, recommended and broken information. It examines JSON-LD blocks individually, including nested entities and entities within an @graph. For broken blocks, it identifies line and column and names common causes such as trailing commas, curly quotes and HTML entities. Its property checks distinguish Google-required from recommended fields for Article, Product, FAQPage, Recipe, Event, BreadcrumbList, LocalBusiness and Organization; other listed types are not graded. It also flags non-absolute image URLs, dates outside ISO format and prices containing a currency symbol. The free checker reads server-sent HTML, so it cannot see JSON-LD inserted by JavaScript. It reports microdata and RDFa when present but does not grade them. A valid result does not guarantee a Google rich result, and the tool recommends Google's Rich Results Test for rendered pages and eligibility checks. It is available on web and via API. The plan list includes a free plan and Starter at $39 a month.