Schema markup
Schema markup is structured data added to a page, usually as JSON-LD, that describes what the page is about in a vocabulary machines can read. It is how a search engine learns that a block of text is a question, a breadcrumb or a defined term.
- Also called
- Structured data, JSON-LD, schema.org markup
- Category
- SEO and AEO
- Updated
- November 2026
Schema.org is a shared vocabulary of types and properties, such as Article, BreadcrumbList or DefinedTerm. Markup uses that vocabulary to label what a page already says. Google says its supported formats are equally fine when valid, and that JSON-LD is usually the easiest to implement and maintain, because it lives in its own script block rather than threaded through the HTML.
Search engines use it in two ways: to understand the page, and to decide whether it qualifies for a rich result. Each rich result has its own requirements, and being eligible does not guarantee it will be shown.
Why it matters for a marketing site
Markup removes guesswork for search engines and makes pages eligible for rich results such as breadcrumbs in a listing. It does not rank a page by itself. It also goes stale: a builder plugin can keep marking up a price or a question the page no longer shows, and Google's guidelines ask that markup describe what is on the page.
How I handle it
On this site, markup and page come from one source so they cannot disagree. The breadcrumb trail is built by one function, and a build check compares the visible trail to the marked-up one on every page, because they once differed. FAQ markup comes from the same array the page renders. This page's DefinedTerm markup comes from the same field as the definition above.
Example
Say a page shows a trail reading Resources, then Glossary. Its BreadcrumbList names those same two items in the same order, with their URLs. If the visible trail said Fintech and the markup said Webflow for fintech companies, the markup would be describing a page that does not exist.
Common mistakes
- Marking up what is not on the page. Structured data should describe visible content. Hidden or invented claims can cost you eligibility.
- Adding FAQ markup for the rich result. Since 2023 Google shows FAQ rich results only for well-known government and health sites. It can still help other readers, but it will not earn that display.
- Pasting it by hand per page. Hand-kept JSON-LD goes stale. Generate it from the data that fills the template.
Questions
Does schema markup help with AI answers?
Google says no special schema is needed for its AI features, though structured data still earns rich results in search. Other assistants have not published an equivalent rule, so accurate markup is reasonable and a guarantee is not.
Which format should I use?
JSON-LD for almost everything. It sits in one script block apart from the page's HTML, so it is easy to generate and to test.
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Where this shows up in my work
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