Structured data check

Do4U checks the structured data of a page. You enter an address or paste the HTML or a JSON-LD block. Do4U reads all JSON-LD blocks (also @graph, lists and nested items), microdata and RDFa, and the code checks them: syntax errors with line and column, unknown or misspelled types, the properties Google requires or recommends for products, articles, breadcrumbs, organizations, local businesses, events, recipes, videos, job postings, reviews and software apps, and the formats of addresses, dates, prices, currencies and ratings. It also warns when a name or price in the markup does not appear in the visible text. You get a tree of the items with errors, warnings and the source of each rule. No AI is used, and the check is free.

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Who it is for

For website owners, shops, agencies and developers who add structured data to their pages and want to find mistakes before search engines do.

Typical uses

Check product pages before a shop launch
Find JSON-LD syntax errors with line and column
Check markup after a plugin or theme update
Compare prices in the markup with the visible prices

Example

Input

Result

S1 Product – Blue mug: Error Merchant listing: the required property image is missing. S2 Offer: Error price: 12,90 is not a number. Write the price with a point for decimals (for example 12.90). priceCurrency: € is not an ISO 4217 currency code (for example EUR). Warnings: recommended properties are missing, for example aggregateRating, brand.name, sku.

A fixed example, shortened. Real results are AI-generated: please check them.

Price and limits

Price: free, without sign-up
Available with: Free, With package
Input limit: One page with up to 300,000 characters of HTML

Privacy

Processed on our own servers in the EU (Poland). Inputs and results are deleted after 7 days (Free) or 30 days (packages), or right after you see the result if you choose not to store them. Images are deleted right after processing.

In the API

Tool name: structured_data_check. Create a job with POST /api/v1/jobs and fetch the result with GET /api/v1/jobs/{id}. You find your API key in your account.

curl -X POST https://do4u.eu/api/v1/jobs \
  -H "Authorization: Bearer d4u_…" -H "Content-Type: application/json" \
  -d '{"tool": "structured_data_check", "url": "https://example.com/"}'

Full API documentation →

Questions and answers

Will my page get a rich result?

No tool can promise that. Do4U checks the markup against the rules Google documents for each type. Whether a rich result appears is decided by Google.

Which formats are read?

JSON-LD in full, including @graph and @id references, plus microdata and RDFa at the level of types and properties. The page is read as the server delivers it, without JavaScript.

What about FAQPage markup?

Google no longer shows FAQ rich results since 7 May 2026. Do4U still reads FAQPage as valid schema.org and adds a note.

Is my text stored?

Only as long as needed: 7 days on Free, 30 days with a package – or not at all if you choose not to store it. Processing happens on our own servers in the EU (Poland).

Can I use the result right away?

Results are AI-generated. Please read them before you publish or send them.

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