JSON-LD Structured Data
Also known as: JSON-LD · Linked data (broader concept) · schema.org markup (common usage)
Definition
JSON-LD (JavaScript Object Notation for Linked Data) is a method of encoding linked data using JSON, standardized by the World Wide Web Consortium (W3C). In web publishing and SEO, JSON-LD is the recommended syntax for embedding schema.org structured data in web pages — machine-readable descriptions of entities (Person, Organization, LocalBusiness, Article, DefinedTerm, etc.) that search engines parse to understand page content. A JSON-LD block typically appears as a <script type="application/ld+json"> element in page HTML, expressing entity types, attributes, and relationships including sameAs links to canonical identity references. (W3C — JSON-LD 1.1)
Identities
| Source Type | Identity |
|---|---|
| Wikipedia | JSON-LD |
| Wikidata | JSON-LD (Q16928008) |
| DBpedia | N/A |
| ProductOntology | N/A |
| Wiktionary | N/A |
| LCSH | Linked data |
| MeSH | N/A |
| NCBI Taxonomy | N/A |
| AGROVOC | N/A |
| Google Scholar | JSON-LD schema.org structured data SEO |
| ConceptNet | N/A |
| OpenCyc | N/A |
Also Known As
- JSON-LD
- Linked data (broader concept)
- schema.org markup (common usage)
Usage Scenarios
1. Entity Markup for Search
Sites declare organizational or personal entities with sameAs arrays for knowledge-graph consolidation.
2. Rich Results
Articles, products, events, and FAQs marked up for enhanced search display.
3. Reference-Site Entity Publishing
Reference wikis (including wiki.org.ph) emit schema.org DefinedTerm graphs with identity and sameAs data — the machine-readable layer of entity SEO.
Strategies
- Match @id values across blocks for graph merging.
- Keep marked-up facts identical to visible page facts.
Security and Safety Measures
- Escape user content properly within JSON to avoid injection.
- Keep markup truthful — mismatches with visible content violate search guidelines.
Historical Context
JSON-LD 1.0 was W3C-recommended in 2014 (1.1 in 2020). Google’s 2015+ shift to JSON-LD as preferred structured-data syntax made it the standard vehicle for schema.org markup.
Challenges and Controversies
Markup Trust
Search engines discount markup contradicted by page content.
Schema sprawl
Over-marking irrelevant properties dilutes signal.