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JSON-LD checker

Find the JSON-LD in a page.
Check it parses.

Paste a page's HTML or a JSON-LD snippet and see every structured data block, whether it parses, and which types it declares.

    Syntax and structure only, based on Google's structured data introduction, read 7 October 2026. It does not check properties against a type (for that, try the structured data property checker) or whether Google will show a rich result. Runs in your browser; nothing is sent anywhere. Then test the live page with Google's Rich Results Test.

    Related: Google's structured data guidelines · which structured data Google still shows rich results for. Per-type rules: review snippets, product snippets and site names.

    More tools: Schema markup generator · Article schema generator · Breadcrumb schema generator · Meta tag checker · All free tools

    Free, no account, nothing leaves your browser.

    How to use it

    1. 1
      Paste the page HTML or the JSON-LD itself

      Paste a whole page source (view-source, or the HTML your CMS outputs) or just the JSON. The tool finds every script block of type application/ld+json; if there is no HTML, it treats your text as one JSON-LD block.

    2. 2
      Read the block list

      Each block is parsed on its own. You get either the JSON syntax error, or its @context, the @type of each item (including items inside @graph), and notes such as a missing @context or @type.

    3. 3
      Validate the content separately

      This tool checks syntax and structure only. Use the Rich Results Test and the Schema Markup Validator to check properties against the type.

    Questions

    What does this tool check?

    It extracts script tags of type application/ld+json from the HTML you paste, parses each one as JSON, and lists the @context, the @type values and the number of items in @graph. It reports JSON syntax errors with the message your browser gives, and notes a missing @context or @type.

    Does Google recommend JSON-LD?

    Google says: "In general, Google recommends using JSON-LD for structured data if your site's setup allows it, as it's the easiest solution for website owners to implement and maintain at scale." (Google's structured data introduction, read 7 October 2026.)

    Where can JSON-LD go in a page?

    Google describes JSON-LD as a notation embedded in a script tag in the head and body elements of an HTML page, and says it can read JSON-LD that is injected dynamically by JavaScript. This tool only sees the text you paste, so JSON-LD added by scripts at load time will not be in a copy of the raw source.

    Does passing this check mean I get rich results?

    No. Valid JSON is only the first step. Whether markup is eligible depends on the properties each Google feature documents, and Google makes no promise to show a rich result. Test the live page with the Rich Results Test.

    Why does it say the JSON is invalid?

    Common causes are a trailing comma, single quotes instead of double quotes, an unescaped double quote inside a string, a comment, or a template placeholder left in the text. The message shown comes from your browser's JSON parser.

    Is the pasted HTML run or sent anywhere?

    No. The HTML is parsed with the browser's DOMParser, which does not run scripts or load images, and nothing is sent to a server.

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