Structured data
Also known as: Schema markup, Schema.org, JSON-LD, Rich snippets markup
Structured data is information on a page, such as a business, person, product, article or FAQ, marked up with the schema.org vocabulary, usually in JSON-LD, so that search engines and other software can read it directly.
A person looking at a page can easily tell which text is the address, which is the phone number and which is a lawyer’s name. Software can’t always. Structured data labels that information explicitly: “This is a law firm, here is its name and address, and these people work here.”
How it’s written
The most widely used vocabulary is schema.org, launched in 2011 by Google, Microsoft, Yahoo and Yandex. Google recommends JSON-LD as the format. It goes into a <script type="application/ld+json"> block in the page’s <head> or body and doesn’t change what visitors see.
Common types include Organization, LocalBusiness, Person, Product, Article, FAQPage and BreadcrumbList.
Why it matters
Google uses structured data for rich results such as review stars, FAQs and product details. Its effect on AI answers is less clear; the companies behind them don’t share much detail. Still, describing an entity clearly and consistently makes it easier for both search engines and language models to recognize a brand correctly. The markup must match what’s visible on the page; marking up content users can’t see goes against Google’s guidelines.
Example
Adding a MedicalClinic JSON-LD block to a clinic’s page, with its name, address, phone number, opening hours and doctors, reduces the chance of machines misreading those details. See our guide to structured data for AI for more.