What is structured data
Also known as: schema markup, schema.org markup, JSON-LD
Structured data is a block of code, invisible to visitors, that describes a page's content in a standard format search engines understand: this is a product, this is the price, this is the date, this person wrote it. The most widely used vocabulary is schema.org, and the format Google recommends in most cases is JSON-LD.
On an article page, inside a script tag of type application/ld+json, goes a block like this: {"@context": "https://schema.org", "@type": "Article", "headline": "What is CAC", "datePublished": "2026-09-24T10:59:00-03:00", "author": {"@type": "Person", "name": "Author name"}}
Visitors see none of it. The search engine reads that the page is an article, with that headline, published on that date and time, by that person. Every piece of marked up information also has to be in the page's visible text.
What it is for
The first use is helping search engines understand the page without guessing. A number can be a price, a rating or a phone number; once marked up, it is no longer ambiguous.
The second is making the page eligible for rich results, the listings with stars, prices, dates or breadcrumbs. Google's documentation also notes that properties it does not use may still be useful for other search engines, tools and platforms.
The three formats
For Google, all three are equally fine as long as the markup is valid and follows each type's documentation. JSON-LD wins in practice because it stays separate from the layout: the site's design can change without breaking the markup.
| How it works | Note | |
|---|---|---|
| JSON-LD | A separate block in a script tag, not mixed into the text | Recommended by Google in most cases |
| Microdata | Attributes inside the visible HTML tags | Valid, but harder to maintain |
| RDFa | Attributes from an HTML5 extension | Valid, more common in older systems |
The types businesses use most
- Organization: name, logo, contacts and official profiles. It can show up in the knowledge panel.
- LocalBusiness: address, opening hours and service area of a local business.
- Product: price, availability and reviews of a product.
- Article: headline, published and modified dates, authorship and images.
- BreadcrumbList: the page's path within the site.
- Event, JobPosting and VideoObject: events, job openings and videos.
The rules Google enforces
Sites that break the rules can get a manual action. The page loses eligibility for rich results without changing its ranking in regular search.
- Only mark up what visitors can see on the page.
- Describe the page's main content, not something secondary.
- Do not mislead: the marked up price, rating or date must match the text.
- Fill in every required property for the type.
- Test with the Rich Results Test and follow the Search Console reports, because markup can break after a site change.
Structured data and AI search
Many consultants started selling special markup to appear in AI answers. Google's AI optimization guide says otherwise: structured data is not required for the generative AI features in Search, and there is no special schema.org markup for them.
The same guide recommends keeping structured data as part of SEO, because it makes pages eligible for rich results. And it asks that markup match the visible text, the same rule as always.
Frequently asked questions
What is structured data?
Code, invisible to visitors, that describes a page's content in a standard format search engines understand, such as product, price, author and date.
Are structured data and schema markup the same thing?
Nearly. Schema.org is the vocabulary, the list of types and properties. Structured data is the markup built with that vocabulary, usually in JSON-LD.
Which format should I use?
JSON-LD, in most cases. It is the format Google recommends and the easiest to maintain, because it stays separate from the visible HTML.
Does structured data improve rankings?
It helps Google understand the page and makes it eligible for rich results. Ranking still depends on the content's relevance and quality.
Do I need structured data to appear in Google's AI features?
No. Google says there is no requirement and no special markup for the AI features in Search, but it recommends keeping markup for the rich results benefit.
Related terms
- Rich snippetsRich snippets are Google results that show more than a title, URL and description: review stars, a product's...
- Knowledge panelA knowledge panel is the information box Google shows when someone searches for an entity in the Knowledge...
- Featured snippetA featured snippet is the box where Google reverses the format of a result: it shows the answer first, taken...
- SERPSERP stands for search engine results page, the page a search engine shows after a query. On Google, it...
- Canonical tagA canonical URL is the version Google picks as the main one when the same content exists at several...
- SitemapA sitemap is a file, almost always in XML, that lists a site's pages, videos and other files and provides...
Rodrigo Fávaro
Founder of ROO3, a marketing and technology agency in São José do Rio Preto, Brazil. Builds AI products running in production (Tobia, gerar.app, Pense Mercado) and maintains the AI Benchmark, a public ranking of AI models.
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