---
title: "What Is Structured Data (JSON-LD)? Definition & Use"
description: "Structured data is machine-readable markup (usually JSON-LD with Schema.org) that helps engines understand a page. It powers Google rich results — but barely affects AI citations."
canonical: https://aiovsseo.com/glossary/structured-data.html
date: 2026-06-07
---
# What is Structured data (JSON-LD)?

Definition

Structured data is machine-readable markup, usually JSON-LD using the Schema.org vocabulary, that describes a page’s content to engines. It powers Google rich results, but has minimal measured effect on AI citations.

**Structured data** is code you add to a page to describe its meaning to machines — an article, an FAQ, a product, a breadcrumb. The recommended format is **JSON-LD** (a `<script type="application/ld+json">` block) using the Schema.org vocabulary.

## What it actually does

Its proven value is **Google rich results**: FAQ snippets, article cards, star ratings, breadcrumbs. What it does *not* meaningfully do is increase AI citations — Ahrefs tracked 1,885 pages adding schema across 2025–2026 and saw no real uplift on AI Overviews, AI Mode or ChatGPT.

## Implement it correctly

Inline JSON-LD in the server-rendered HTML. Avoid injecting it after client-side hydration, and avoid microdata on collapsed accordions. Details in [metadata LLMs actually read](/articles/metadata-llms-read.html).

## Frequently asked questions

**Does structured data help with AI citations?**

Barely. Controlled measurement shows schema markup has near-zero effect on whether AI engines cite a page. It remains valuable for Google rich results, but it is not a citation lever.

**What is the best format for structured data?**

JSON-LD, inline in the server-rendered HTML, using Schema.org types. Google recommends JSON-LD over microdata because it is decoupled from visual rendering.