Schema.biz vs StructuredValidator

Schema.biz is a free browser toolkit for structured data markup, database schemas, and API specifications. Its markup tools generate, validate, and optimize JSON-LD, Microdata, and RDFa. A visual schema designer exports SQL for PostgreSQL, MySQL, SQLite, and SQL Server; database tools also diagram CREATE TABLE statements, compare schema versions, visualize queries, and offer templates. API tools validate JSON Schema, edit OpenAPI specifications, generate schemas and mock data, convert formats, and detect breaking changes. An AI Search Optimizer checks structured data readiness for ChatGPT Search, Perplexity, and Google AI Overviews. Pasted data is processed in browser JavaScript, and the maker says it is not sent to its servers. For URL-based markup checks, however, the server fetches the requested page for the browser to inspect. The free plan includes all tools without feature gates, limits, or signup. Persistent cross-device work and third-party URL crawling are not offered; an API Validator and Mock Server are marked as coming soon.

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.