Structured data and schema markup: what helps, what doesn’t

The numbers in the “Sources” column refer to the source list at the end of this article. So far, studies on structured data for AI search come from vendors of SEO and analytics tools. Ahrefs compared 1,885 pages that added JSON-LD between August 2025 and March 2026 with 4,000 similar pages. Afterward, the pages with markup were cited 2.4% more often in AI Mode and 2.2% more often in ChatGPT. Neither difference was statistically significant. In AI Overviews, they were cited 4.6% less often, but both groups had already been losing citations there. Ahrefs only studied pages that AI systems were already citing heavily. Whether markup helps pages that AI systems don’t cite at all yet remains an open question.

Source: Ahrefs (external site), May 11, 2026 · vendor study · 1,885 pages, 4,000 control pages, 30 days before and after

When an AI assistant fetches a page directly, it apparently picks up little from the JSON-LD. In a searchVIU test on October 30, 2025, none of five systems named a price that appeared only in the JSON-LD. A test that OtterlyAI published in March 2026 painted a similar picture: when asked, only Gemini out of seven platforms reproduced the JSON-LD correctly. FAQ markup didn’t show an advantage in an SE Ranking analysis either. Pages with FAQ markup averaged 3.6 citations in ChatGPT, while pages without it averaged 4.2.

Source: searchVIU (external site), Dec 2, 2025 · vendor study · test of Oct 30, 2025, eight price sources, five AI systems

Source: OtterlyAI (external site), Mar 23, 2026 · vendor study · its own website, seven platforms

Source: SE Ranking (external site), Nov 24, 2025 · vendor study · 129,000 domains, correlation without proof of cause

For the current state of evidence on generative engine optimization (GEO), meaning visibility in AI answers, see What’s proven about GEO, and what isn’t? in our GEO guide. Our explainer on AI Overviews covers which pages are eligible as sources.

Schema.org is a shared vocabulary that Google, Microsoft, Yahoo and Yandex founded and that an open community continues to develop (Schema.org home page (external site)). That’s why structured data is also known as schema markup. The vocabulary comprises 826 types and 1,540 properties. JSON-LD is a JSON-based format for linked data. Version 1.1 has been a W3C Recommendation since July 16, 2020 (JSON-LD 1.1 (external site)). The W3C is the organization where web standards are developed (W3C (external site)).

Source: Schema.org, Sep 16, 2026 · version 30.1

Here’s how a small business could mark up its company details on its home page:

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Organization",
  "@id": "https://www.example.com/#organization",
  "name": "Example GmbH",
  "url": "https://www.example.com/",
  "logo": "https://www.example.com/logo.png",
  "email": "info@example.com",
  "address": {
    "@type": "PostalAddress",
    "streetAddress": "Example Street 1",
    "postalCode": "12345",
    "addressLocality": "Anytown",
    "addressCountry": "DE"
  }
}
</script>

@context names the vocabulary and @type the type; the remaining lines are properties. @id gives an entry a fixed identifier that other entries can point to, for example an article to its author. Google recommends such references for entries that belong together (Google’s general guidelines (external site)).

About half of the web pages studied carry structured data. Web Data Commons, a project of the University of Mannheim, found it on 1.3 billion of 2.4 billion pages in the October 2024 Common Crawl. Common Crawl is a free archive of web pages that anyone can use. In its July 2025 crawl, the HTTP Archive found structured data on 50% of home pages and JSON-LD on 43%.

Source: Web Data Commons (University of Mannheim) (external site), Jan 10, 2025 · Common Crawl of October 2024, 51.25% of pages

Source: HTTP Archive, Web Almanac 2025 (external site), Jan 15, 2026, updated Jun 9, 2026 · home pages, July 2025 crawl

Our technical SEO guide explains where structured data fits alongside crawling, indexing and page speed.

For the home page of a company website, Google recommends Organization markup. It helps Google understand a company’s administrative details and tell it apart from other companies (Google on Organization markup (external site)). Experts call such a clearly identifiable thing, like a company or a person, an entity. Some properties work only behind the scenes. Others help determine which logo Google shows in the knowledge panel, the information box about a company. Why consistent company facts matter to AI assistants as well is covered in the step Are your company facts clear and consistent everywhere? of our ChatGPT how-to. Our article Entity SEO explains why AI systems mix up companies.

With WebSite markup on your home page, you tell Google which site name to show above your pages in search results. Google also looks at titles and headings for this but gives the WebSite data the most weight (Google on site names (external site)). According to Google, Article markup helps it show better titles, images and dates for articles (Google on Article markup (external site)).

To show that rich results can bring clicks, Google points to case studies from major brands. Rotten Tomatoes, for example, added structured data to 100,000 pages and measured a 25% higher click-through rate on them than on pages without it. The four examples on Google’s introduction page aren’t dated.

Source: Google Search Central (external site), Dec 10, 2025 · case study without its own date

According to Google, markup that it no longer uses doesn’t cause problems in Search (Google, Oct 21, 2024 (external site)). It has no visible effect either, and Google says the removals didn’t affect rankings. Many websites still carry it: in July 2025, the HTTP Archive found the SearchAction type for the discontinued search box on 28% of home pages.

Source: HTTP Archive, Web Almanac 2025 (external site), Jan 15, 2026, updated Jun 9, 2026 · home pages, July 2025 crawl

For a result’s preview image, Google considers the primaryImageOfPage property in schema markup as well as the og:image tag (Google on images (external site)). Our explainer llms.txt: what it does and what it doesn’t covers the file in detail.

Google gives an example: if the JSON-LD describes a performer, the visible text must describe the same performer. You may not mark up content that visitors can’t see, fake reviews or content unrelated to the page (Google’s general guidelines (external site)). Search Console reports such cases in the Manual actions report, for example as “Structured data found on hidden content” (Search Console Help on manual actions (external site)). Bing requires the same and may ignore misleading markup (Bing Webmaster Guidelines (external site)).

For AI assistants, there’s also a practical reason. In tests where systems fetched a page directly, details that appeared only in the markup almost never made it into an answer. So prices, business hours, and questions and answers belong in the visible text first. The markup then describes them.

1. Stars for yourself: Reviews of your own company don’t make pages with Organization or LocalBusiness data eligible for review stars, even if the reviews come from a Google or Facebook widget. Since July 24, 2026, Google has also explicitly ruled out fake reviews and undisclosed incentivized reviews (Google on review snippets (external site)).
2. Contradictions: A price or a date in the markup differs from the one on the page, often after an update that only reached one of the two places. Google requires, for example, that visible dates and marked-up dates match (Google on byline dates (external site)). The fix: generate the text and the markup from the same source.
3. Markup only via JavaScript: A plugin or tag manager adds the JSON-LD only in the browser. Google reads it after rendering, but for products it warns that this can make Shopping crawls less frequent and less reliable (Google on JavaScript markup (external site)). In a Vercel measurement from late 2024, the crawlers of OpenAI, Anthropic and Perplexity didn’t execute JavaScript (Vercel (external site)). There’s more on this in the step Are your services visible in the HTML? of our ChatGPT how-to.
4. Unsuitable type: For LocalBusiness, Google requires the address of the business (Google on LocalBusiness (external site)). Schema.org lists the ProfessionalService type as deprecated (ProfessionalService on Schema.org (external site)). Google advises using the most specific type that actually fits.
5. Incomplete or invalid markup: If a type is missing required properties, the page isn’t eligible for that rich result. The Rich Results Test ignores comments in JSON-LD. The JSON-LD standard doesn’t support them, though, so in actual use they can cause errors (Search Console Help on the Rich Results Test (external site)).
6. Wrong expectations: Many see markup as a lever for citations in AI answers, but there’s no evidence for that. You don’t need to remove outdated markup such as FAQPage or HowTo; according to Google, it doesn’t cause problems (Google on HowTo and FAQ (external site)).

1. View the source code: In Chrome, press Ctrl+U on Windows or Linux to open a page’s HTML source, or Command+Option+U on a Mac (Chrome Help (external site)). Search it for application/ld+json. If the block is missing even though a plugin adds structured data, the plugin probably creates it with JavaScript.
2. Rich Results Test: Google’s tool tests a URL or a code snippet and shows the types it detected, with errors and warnings. It fetches the page as Google-InspectionTool, by default with the smartphone user agent. Its code explorer shows the rendered source code, meaning the page after JavaScript has run (Search Console Help on the Rich Results Test (external site)).
3. Schema Markup Validator: The Schema Markup Validator (external site) checks syntax and vocabulary, including types that Google doesn’t use. It doesn’t check whether a page is eligible for rich results (Google, Dec 15, 2020 (external site)).
4. Compare with the page: Check by hand that every value in the markup appears on the page and reads the same. According to Google, its quality guidelines for structured data can’t easily be tested with automated tools.
5. Monitor Search Console: Under Enhancements, Search Console has a report for each rich result type with a sample of the detected items. The URL Inspection tool shows individual pages (Search Console Help on rich result reports (external site)). To set up Search Console, follow the step Have you set up Google Search Console? in our how-to on websites that don’t show up on Google.
6. Measure the effect: Google recommends marking up a few frequently visited pages and comparing their performance over a few months with the period before. For citations in AI answers, Ahrefs also recommends control pages that don’t get markup during the same period.

Carousels: They show several entries from a single website side by side, each tile with details such as price, rating and image. To be eligible, a summary page needs ItemList markup combined with LocalBusiness, Product or Event. The feature is in beta and available only in EEA countries, Türkiye and South Africa (Google on carousels (external site)). Searchers in other countries don’t see it. The EEA comprises the 27 EU member states plus Iceland, Liechtenstein and Norway (EUR-Lex glossary (external site)). Carousels matter for retailers, event organizers and directories, not for a company website without such listings.

Events: Only events that the public can book and that take place at a physical location are eligible. Google doesn’t support purely online events (Google on events (external site)).

VAT ID: If your company has a VAT identification number, you can add it to Organization as vatID. Google calls it an important trust signal because users can look up your business in public VAT registries (Google on Organization markup (external site)). Make sure all details match your legal notice and your entries in business registers.

Digital Product Passport: With version 30.0 of March 19, 2026, Schema.org published examples for the EU’s Digital Product Passport. Version 30.1 of September 16, 2026, adds the DigitalProductPassport type, which products and offers can carry (Schema.org releases (external site)). Google’s documentation on products doesn’t mention it yet (Google on merchant listings (external site)). Which products need such a passport is a legal question that this article doesn’t answer.