Structured data
JSON-LD Syntax and Required-Property Checker
Paste JSON-LD, or a whole page, and see syntax errors with line numbers plus missing required and recommended properties for each Google type.
Runs in your browser; nothing is uploaded. · Free, no account · 3 min
Paste the JSON itself, or the page source: every script tag of type application/ld+json is checked.
Importing a saved run into your account is coming soon. Until then, your last runs stay in this browser only, and you can download your files.
How to use
- Paste the JSON-LD, or the source of a page that contains script tags.
- Read the syntax errors first: each one has a line and column.
- Fix the required properties, then the recommended ones and the value warnings.
- Check again until the report shows no errors, then test the live page with Google's tools.
What it checks and how it works
The checker works in three steps. First it parses strict JSON with the jsonc-parser library and reports each error with line and column, since Google reads JSON-LD as JSON (RFC 8259). Then it checks structure: @context, @type, and the type names against the schema.org vocabulary, release 30.1 of 16 Sep 2026, so a misspelt or wrongly cased type is named. Then it checks each node against the required and recommended properties on the Google Search Central page for its type, opened on 29 Oct 2026, including either-or rules such as Product needing one of review, aggregateRating or offers.
For FAQPage and HowTo it states that Google no longer shows the rich result, and for Service and other types with no Google feature it says so and uses schema.org minimums, labelled as Zaher's. It does not fetch your page, run its JavaScript, test eligibility or judge whether the markup matches what readers see, which Google's guidelines require. Use Google's Rich Results Test for the final check.
Sources
- Google Search Central: Intro to how structured data markup works opened 29 Oct 2026
- Google Search Central: Search gallery of structured data features opened 29 Oct 2026
- W3C: JSON-LD 1.1 opened 29 Oct 2026
- RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format opened 29 Oct 2026
- schema.org vocabulary, release 30.1 (16 Sep 2026), CC BY-SA 3.0 opened 29 Oct 2026
- Google Search Central: General structured data guidelines opened 29 Oct 2026
Related tools
Microdata, RDFa and JSON-LD Detector
Paste a page's HTML and see every item of structured data in all three syntaxes, with its type, properties, line number and gaps.
JSON-LD Minifier and Prettifier
Indent JSON-LD for reading or compress it for your page, with every number and string copied exactly as written.
Organization Schema Generator
Fill in your organization's details and get JSON-LD that follows Google's Organization structured data page.
Product and Offer Schema Generator
Enter a product and its offer and get Product JSON-LD that follows Google's merchant listing and product snippet pages.
Go further with Zaher: See how Zaher's SEO Engine audits technical SEO
Questions
About this tool
No. Google does not guarantee that structured data produces a result, and the markup must also match the visible page. The report only says the syntax and listed properties pass.
Plain JSON-LD, an array, an object with @graph, or a full page with one or more script tags of type application/ld+json. Each block is checked.
The markup is still valid schema.org. The warning tells you that Google no longer shows the rich result, with the dates from its own pages.
Get started today
Find out where your brand stands in AI. Free.
Run a free AI visibility analysis on your domain. No credit card, results in minutes. See what AI engines say about your brand today.
Brands already measuring their AI visibility with Zaher.
