STRUCTURED DATA · SEO GLOSSARY
JSON-LD
JavaScript Object Notation for Linked Data — Google\'s preferred format for adding structured data (Schema.org markup) to web pages via a `<script type="application/ld+json">` block in the HTML head or body, keeping machine-readable data separate from visible content and easier to maintain than Microdata or RDFa.
Definition
JSON-LD (JavaScript Object Notation for Linked Data) is a W3C standard for embedding machine-readable structured data into web pages. It uses JSON syntax within a `<script type="application/ld+json">` tag to describe the content of the page in terms of Schema.org vocabulary. Google, Bing, and other search engines parse JSON-LD to extract entity information for Rich Results, Knowledge Panels, AI Overview citations, and other enhanced search features. JSON-LD advantages over other structured data formats: **Separation of concerns** — the JSON-LD block is completely separate from the HTML content, so updating schema doesn\'t require editing visible text or adding attributes throughout the HTML. **Developer-friendly** — JSON syntax is familiar to most developers and easy to generate programmatically. **Easy validation** — the JSON-LD block can be tested independently without rendering the full page. **Google\'s recommendation** — Google explicitly recommends JSON-LD over Microdata and RDFa in its developer documentation. A basic JSON-LD example: `{ "@context": "https://schema.org", "@type": "Article", "headline": "Title Here", "author": { "@type": "Person", "name": "Author Name" } }`. Multiple schema types can appear on one page either as separate `<script>` blocks or within a single block using the `@graph` array. The JSON-LD block can appear in the `<head>` or `<body>` — Google parses both locations. For server-rendered sites, the JSON-LD must be in the raw server HTTP response to be visible to Googlebot\'s first-wave crawl; JavaScript-injected JSON-LD (added by client-side scripts after page load) may be missed in the first crawl.
Why it matters for SEO
JSON-LD is the implementation mechanism for schema markup — without it (or one of the alternative formats), structured data can\'t signal Rich Results eligibility to search engines. Product schema for shopping rich results, FAQPage for FAQ dropdowns, Article for author bylines in Top Stories, and HowTo for step-list rich results all require structured data implementation. JSON-LD is the easiest implementation format to audit and validate because it\'s self-contained in a single block — making it easier to detect errors (missing required properties, invalid enum values) than Microdata attributes scattered throughout HTML.
How DeepSEOAnalysis checks this
The audit extracts all JSON-LD blocks from the raw server HTTP response of every crawled page (not the post-JavaScript DOM), parses the JSON, validates the schema type and required properties against Google\'s Rich Results requirements, checks for common errors (availability values without `https://schema.org/` prefix, numeric prices as numbers rather than strings, aggregateRating.reviewCount of zero), and flags any JSON-LD that appears only in the rendered DOM (client-side injection gap).
Useful tools and resources
GLOSSARY
Related terms
structured data
Structured Data
Machine-readable annotations added to HTML — usually JSON-LD — that explicitly describe what a page is about to search engines and AI systems.
Read definition →structured data
Schema Markup
A shared vocabulary of types and properties from Schema.org used to annotate web content in machine-readable format — enabling search engines to understand what content means, not just what it says, and to generate rich results.
Read definition →structured data
Rich Results
Enhanced search result formats that Google displays beyond the standard blue link, title, and description — including star ratings, FAQ dropdowns, product panels, recipe cards, How To steps, event dates, and job listings — enabled by valid structured data (JSON-LD schema) in the page\'s server-rendered HTML.
Read definition →structured data
Product Schema
Product schema is a Schema.org structured data type that describes a product for sale — name, description, image, price, availability, reviews — enabling rich results including price, availability, and star ratings directly in Google Search results. It is the highest-priority structured data type for e-commerce.
Read definition →See how your site scores on JSON-LD.
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