What Is Schema Markup?

Schema.org was founded by Google, Microsoft, Yahoo, and Yandex to give the web one shared vocabulary for describing page content to search engines. It caught on: as of 2024, more than 45 million web domains carry Schema.org markup, over 450 billion objects in total, by the project's own count. In SEO, "schema" almost always means schema markup: that vocabulary applied to your pages so search results can show more than a plain blue link.

With schema markup you label the facts on a page (prices, ratings, dates, authors) so robots crawling the site can read them directly instead of guessing from your layout.

Schema vs. structured data vs. rich results

Four related terms get used interchangeably, and they stack in a strict order:

• Structured data is machine-readable information about a page's content, written in a standardized format.
• Schema.org is the shared vocabulary for expressing it, developed by an open community process.
• Schema markup is that vocabulary applied to one specific page.
• Rich results, long called rich snippets, are the enhanced listings the markup can earn: star ratings, prices, images, event dates.

Why schema markup matters

Markup makes a page eligible for rich results, and rich results get noticed. In Google's structured data documentation, Rotten Tomatoes added markup to 100,000 pages and measured a 25% higher click-through rate on them than on pages without it. More clicks at the same rankings is the whole pitch, and it's often the cheapest website traffic win available on a page that already ranks.

Eligible is the operative word. Google doesn't guarantee a rich result even when the markup is correct; it decides what to show per query and per page. Treat markup as raising your odds, not buying a feature.

Common schema types and a worked example

Google keeps a feature guide for each type it can show rich results for. These are the ones site owners reach for most:

• Article: news stories and blog posts
• Product: price, availability, and review stars on product pages
• Recipe: cook time, ratings, and an image in the listing
• Review: star ratings drawn from critic or user reviews
• LocalBusiness: hours, address, and contact details
• Event: dates, venues, and ticket information
• BreadcrumbList: the page's position in your site's hierarchy
• Organization: your company's name, logo, and profiles

Here's what the markup itself looks like. A recipe page's JSON-LD, reduced to its key properties:

• @type: Recipe
• name: Sourdough Pancakes
• cookTime: PT20M (an ISO 8601 duration, meaning 20 minutes)
• aggregateRating: ratingValue 4.7, reviewCount 213

From those four lines, a search engine knows the dish, the cook time, and the rating without parsing your page design, and it can print the stars and the minutes right in your listing.

How to add schema markup to your site

Schema.org markup comes in JSON-LD, Microdata, or RDFa. Google recommends JSON-LD where your site's setup allows it, calling it the easiest for site owners to implement: a script block of name and value pairs that sits in the page's HTML without touching the visible layout.

Most site owners never write it by hand. Popular WordPress SEO plugins, Yoast SEO among them, generate common markup such as articles, breadcrumbs, and organization details automatically. For anything custom, Google's Structured Data Markup Helper builds markup from a point-and-click pass over your page, or you can write the JSON-LD yourself. For the full walkthrough, from picking a type to publishing and testing, start with our beginner's guide to schema markup.

Where schema markup goes wrong

Three failure modes account for most wasted markup:

• Markup that doesn't match the page. Structured data has to describe content visitors can actually see. Misleading markup violates Google's content policies and can draw a manual action: the page loses rich-result eligibility until it's fixed, though its ranking isn't affected.
• Silent syntax errors. A missing bracket or required property produces no warning in search; the page just stops being eligible. Retest whenever you change a template.
• Betting on a retired type. Google withdraws rich result types over time: How-to rich results ended in September 2023, and FAQ rich results stopped showing in May 2026. Check Google's current supported-features list before you invest in new markup.