Free Structured Data Checker — detect JSON-LD, Microdata & RDFa
The Structured Data Checker is a free structured data testing tool that fetches
any URL and reveals the schema markup hidden in your page’s HTML. It detects all three supported
syntaxes — JSON-LD, Microdata and RDFa — lists every
schema.org @type found in your JSON-LD blocks, and flags any JSON-LD that fails to
parse. In seconds you get a clear, evidence-based view of exactly what structured data search engines can read on
your page, so you can confirm your SEO markup is present and well-formed before you chase
rich results.
How the Structured Data Checker works
Checking your structured data takes three simple steps:
- Enter your URL. Paste any public web page address into the box above and click Check.
- We fetch and scan the markup. The tool retrieves your live HTML and scans it for JSON-LD, Microdata and RDFa — nothing is guessed or estimated.
- You get an instant report. See which syntaxes are used, the list of schema.org
@typevalues in your JSON-LD, and a warning on any block that does not parse.
What is structured data and schema markup?
Structured data is a standardised way of labelling the information on a page so that machines can understand it, not just display it. Instead of leaving Google to guess that “4.8” is a rating or that a block of text is a recipe, you explicitly describe each entity — a product, an article, an FAQ, a local business — using an agreed vocabulary. That vocabulary is schema.org, a shared standard maintained by Google, Microsoft, Yahoo and Yandex. When people talk about “schema markup”, they mean structured data written with the schema.org vocabulary. Adding it does not change how your page looks to visitors; it adds a machine-readable layer that helps search engines interpret your content accurately.
JSON-LD vs Microdata vs RDFa
The same schema.org vocabulary can be written in three syntaxes, and this checker detects all of them:
JSON-LD (recommended)
JSON-LD (JavaScript Object Notation for Linked Data) keeps your structured data in a single
<script type="application/ld+json"> block, cleanly separated from your visible HTML. Google
recommends JSON-LD because it is the easiest to add, read and maintain — you can inject or update
it without touching your page layout. If you are adding schema for the first time, use JSON-LD.
Microdata
Microdata embeds the markup inline using HTML attributes such as itemscope,
itemtype and itemprop. It is fully supported but harder to maintain because the data is
interleaved with your content, so a template change can easily break it.
RDFa
RDFa (Resource Description Framework in Attributes) also lives inline, using attributes like
vocab, typeof and property. Like Microdata, it is valid and supported, but
JSON-LD remains the simplest choice for most sites.
How schema powers rich results in Google
Valid schema markup makes your pages eligible for rich results — the enhanced listings, also known as rich snippets, that stand out on the Google search results page. Depending on the schema.org type you use and Google’s requirements, structured data can unlock features such as:
- Review stars from
ReviewandAggregateRatingmarkup. - FAQ drop-downs from
FAQPagemarkup. - Breadcrumbs from
BreadcrumbListmarkup. - Product listings with price, availability and ratings from
Productmarkup. - Article details with headline, author and publish date from
Articlemarkup.
Eligibility is not a guarantee: Google decides whether to display a rich result, and it only does so when the markup is accurate and meets the requirements for that feature. That is exactly why checking your structured data first matters — you want to confirm the markup is present and parses before you expect any snippet.
Common schema.org types
Some of the most widely used schema.org types include Organization,
WebSite, WebPage, Article, Product, Review,
AggregateRating, FAQPage, BreadcrumbList, LocalBusiness,
Person, Recipe, Event and VideoObject. This tool lists the
@type values it finds in your JSON-LD so you can confirm you have marked up the right entities.
How to validate structured data and avoid errors
Detecting your markup is the first step; validating it is the second. A single malformed JSON-LD block — a trailing comma, an unclosed brace, a stray quote — can stop search engines parsing it entirely, which is why this checker flags any JSON-LD block that fails to parse. Once your markup is detected and parses cleanly, confirm it against the requirements for the specific rich result you are targeting using Google’s Rich Results Test and the schema.org validator, both of which check required and recommended properties.
Structured data best-practices checklist
- Prefer JSON-LD for new markup — it is the syntax Google recommends.
- Use accurate schema.org
@typevalues that match the real content of the page. - Only mark up content that is actually visible to users on the page.
- Make sure every JSON-LD block is valid JSON so it parses without errors.
- Include the required and recommended properties for the rich result you want.
- Re-check after every template or CMS change, since inline Microdata and RDFa break easily.
Common structured data mistakes
- Broken JSON-LD that fails to parse because of a syntax error, so search engines ignore it.
- Marking up content that is not visible on the page, which violates Google’s guidelines.
- Choosing the wrong schema.org
@typefor the entity being described. - Missing required properties, making the page ineligible for the rich result.
- Mixing multiple syntaxes inconsistently instead of standardising on JSON-LD.
- Assuming valid markup guarantees a rich snippet — eligibility is never a guarantee.
Ready to round out your on-page audit? Pair this structured data checker with our Meta Tags Analyzer to review your title, description and social tags, then run a full Website SEO Checker report to audit headings, content, links and markup in one place.
Frequently asked questions
What is a structured data checker?
A structured data checker is a free tool that fetches a URL and detects the structured-data markup embedded in the page. It looks for all three supported syntaxes — JSON-LD, Microdata and RDFa — lists the schema.org @type values it finds inside JSON-LD blocks, and flags any JSON-LD that fails to parse. Everything is observed directly from the page markup, so you can confirm exactly what search engines see.
What is the difference between JSON-LD, Microdata and RDFa?
They are three different syntaxes for expressing the same schema.org vocabulary. JSON-LD keeps the markup in a single <script type="application/ld+json"> block, separate from your HTML. Microdata and RDFa embed the data inline using HTML attributes such as itemscope, itemtype and itemprop (Microdata) or vocab, typeof and property (RDFa). Google supports all three, but recommends JSON-LD because it is the easiest to add and maintain.
What are rich results and how does schema markup enable them?
Rich results (also called rich snippets) are enhanced search listings — such as review stars, FAQ drop-downs, breadcrumb trails, product pricing and article details — that Google can display when a page has valid, eligible schema markup. Adding accurate structured data makes a page eligible for these features, but eligibility never guarantees that Google will display them.
Does this structured data testing tool validate my markup against Google requirements?
This checker reports what structured data is present on the page: which syntaxes are used, which schema.org types appear in JSON-LD, and whether any JSON-LD block fails to parse. It is a fast way to see and sanity-check your markup. For a full eligibility check against a specific rich-result type, also run Google’s Rich Results Test and the Schema.org validator, which test required and recommended properties.
Is the structured data checker free?
Yes, it is completely free with no signup. Enter any public URL and get an instant report of the structured data found on the page. Results are observed straight from the live HTML — nothing is invented or estimated.