JSON-LD vs Microdata schema comparison: when to use each, the key differences, and the common confusions.
JSON-LD is Google's preferred format, decouples from page HTML, and is easier to validate. Microdata works but constrains HTML structure and is harder to maintain across template refactors. Choose JSON-LD for new implementations.
Use JSON-LD when the entity matches the schema definition specifically and the visible page content is dominated by JSON-LD-shaped content. Validate with Schema.org Validator before deployment to confirm scope alignment.
Use Microdata when the entity matches the Microdata definition specifically. Don't ship both JSON-LD and Microdata schema on the same page unless both blocks are independently visible — that creates schema scope mismatch and risks downgrading rich-result eligibility for both.
The most common mistake is shipping the wrong schema for the dominant content block — e.g., Microdata schema on a page where the visible content is JSON-LD-shaped. The validation gate catches this if you run Schema.org Validator + a manual check that the schema matches the visible DOM.
Only if both blocks are independently visible on the page. Schema scope must match visible content per Google's rules.
Depends on the query. Informational queries with question-shape favour FAQPage; procedural queries favour HowTo; commerce queries favour Product. Ship the schema matching the page's primary intent.
Default to whichever schema most cleanly describes the dominant visible block. Validate with Schema.org Validator. When in doubt, ship the simpler schema (Article) and add specificity later as you confirm the citation pattern.