JSON-LD Validator
Paste JSON-LD — or a whole HTML page — and check the syntax, types and recommended Schema.org properties. Free, instant, nothing leaves your browser.
What is JSON-LD?
JSON-LD (JavaScript Object Notation for Linked Data) is the format search engines and AI assistants read to understand a page. It sits in a <script type="application/ld+json"> tag and describes the page as structured data — an organisation, an article, a product, a list of FAQs — using the shared Schema.org vocabulary. Google uses it for rich results; assistants such as ChatGPT, Perplexity and Google’s AI Overviews use it to work out what your content actually is.
This validator catches the four mistakes that break structured data most often:
- Invalid JSON — a trailing comma or an unclosed brace stops the whole block from being read.
- A missing or misspelt
@type— without a recognised type, nothing can interpret the node. - Missing recommended properties — an Organization with no logo, an Article with no author, a Product with no price.
- Dangling references and empty values — an
@idthat points nowhere, or fields left as empty strings.
New to structured data? Start with What is JSON-LD? for a plain-English walk-through.
Rather not hand-write any of this? AI Boost for Joomla generates valid JSON-LD for every page automatically — Schema.org, sitemaps, OpenGraph and more.