Application/LD+JSON Explained

When you add JSON-LD to a web page, you wrap it in a <script> tag with a specific type attribute: application/ld+json. This article explains what that MIME type means and why it matters.

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What Is application/ld+json?

application/ld+json is a MIME type (also called a media type or content type) that identifies content as JSON-LD — JSON for Linked Data.

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Article",
  "headline": "Application/LD+JSON Explained"
}
</script>

The type attribute tells the browser: “This is not executable JavaScript. Do not run it. It’s structured data in JSON-LD format.”

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How Browsers Handle It

When a browser encounters <script type="application/ld+json">, it:

1. Does NOT execute the content — Unlike <script> or <script type="text/javascript">, the browser ignores this block during JavaScript execution.
2. Does NOT render it visually — The content is invisible to users.
3. Preserves it in the DOM — The script element is accessible via document.querySelector('script[type="application/ld+json"]').

This is by design. JSON-LD is metadata for machines, not content for humans or instructions for browsers.

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How Search Engines Handle It

Google, Bing, and other search engine crawlers specifically look for <script type="application/ld+json"> elements. When found, they:

1. Parse the JSON content.
2. Validate it against the Schema.org vocabulary.
3. Use the structured data to generate rich results (FAQ dropdowns, star ratings, product cards, etc.).

If you use a different MIME type (e.g., application/json or text/json), search engines will not recognize it as structured data.

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The MIME Type Breakdown

Component	Meaning
application	The data is for programmatic use (not human display)
ld	Linked Data
json	The serialization format is JSON

The full MIME type application/ld+json was registered with IANA (Internet Assigned Numbers Authority) as part of the JSON-LD specification (W3C Recommendation).

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Common Mistakes

Using the Wrong Type

<!-- WRONG — browser will try to execute as JavaScript -->
<script>
{ "@context": "https://schema.org", "@type": "Article" }
</script>

<!-- WRONG — search engines won't recognize this -->
<script type="application/json">
{ "@context": "https://schema.org", "@type": "Article" }
</script>

<!-- CORRECT -->
<script type="application/ld+json">
{ "@context": "https://schema.org", "@type": "Article" }
</script>

Invalid JSON Syntax

Even though the browser doesn’t execute the block, invalid JSON will cause search engine parsers to fail silently. Always validate your JSON syntax.

Multiple Blocks

You can have multiple <script type="application/ld+json"> blocks on a single page. Each one is parsed independently:

<script type="application/ld+json">
{ "@context": "https://schema.org", "@type": "Article", "headline": "..." }
</script>

<script type="application/ld+json">
{ "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [...] }
</script>

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Related Resources

• What Is JSON-LD? — Introduction to JSON-LD.
• Where to Put JSON-LD in HTML — Placement best practices.
• JSON-LD vs JSON — How JSON-LD extends standard JSON.