Schema Markup Generator (JSON-LD)

What Is Structured Data?

Structured data is a standardized format for providing explicit information about a page and classifying its content in a way that search engines can understand programmatically. While search engines are increasingly sophisticated at interpreting natural language, structured data removes ambiguity by declaring exactly what entities exist on a page, their properties, and their relationships to one another.

The most widely adopted structured data vocabulary is Schema.org, a collaborative project founded in 2011 by Google, Microsoft, Yahoo, and Yandex. Schema.org defines hundreds of types (like Article, Product, Person, Organization) and thousands of properties (like name, description, datePublished) that describe the entities on your web pages. When you add schema markup to your pages, you are essentially providing a machine-readable data layer alongside your human-readable content.

The practical benefit of structured data is its ability to trigger rich results (previously called rich snippets) in search engines. Rich results are enhanced search listings that include additional visual elements beyond the standard title, URL, and description. Examples include star ratings for products, cooking times for recipes, expandable FAQ sections, event dates and venues, and step-by-step instructions for how-to content. These enhanced listings consistently achieve higher click-through rates than standard results.

JSON-LD vs Microdata vs RDFa

There are three main formats for implementing structured data on web pages: JSON-LD, Microdata, and RDFa. Each has distinct characteristics that affect implementation complexity, maintainability, and search engine support.

JSON-LD (JavaScript Object Notation for Linked Data) is Google's explicitly recommended format. It uses a separate <script type="application/ld+json"> block that contains all structured data as a JSON object. The key advantage of JSON-LD is its separation from the HTML markup itself. You can add, modify, or remove structured data without touching your page templates. This makes it ideal for content management systems, dynamic pages, and situations where different teams manage content and technical SEO. JSON-LD also supports nesting and referencing, making complex entity relationships straightforward to express.

Microdata embeds structured data directly into HTML elements using attributes like itemscope, itemtype, and itemprop. While it tightly couples the data to the visible content (reducing the risk of discrepancies), it makes the HTML more complex and harder to maintain. Any template change risks breaking the structured data. Microdata was the original format promoted by Google but has been largely superseded by JSON-LD in modern practice.

RDFa (Resource Description Framework in Attributes) is similar to Microdata in that it uses HTML attributes, but follows the RDF specification. It uses attributes like vocab, typeof, and property. RDFa is more commonly used in semantic web applications and government data portals. For SEO purposes, JSON-LD is almost always the better choice due to its simplicity and Google's strong preference for it.

Google Supported Schema Types

While Schema.org defines hundreds of types, Google only generates rich results for a specific subset. Understanding which types are supported and what rich results they enable helps you prioritize your structured data implementation. As documented in Google's structured data documentation, the key supported types include Article (for news and blog content), FAQ (expandable question-answer pairs), HowTo (step-by-step instructions), Product (e-commerce listings with price and availability), LocalBusiness (business listings with address and hours), and many more.

Article schema is essential for news sites and blogs. It enables enhanced display in Google News and Top Stories carousels. The required properties include headline, datePublished, and author, while recommended properties include dateModified, image, and publisher. FAQ schema creates expandable question-and-answer sections directly in the search results, significantly increasing your listing's visual footprint. Each question-answer pair is defined as a mainEntity item with name (question) and acceptedAnswer (answer text).

Product schema is critical for e-commerce sites, enabling rich product listings with price, availability, review ratings, and more. LocalBusiness schema powers the knowledge panels and map listings that appear for local search queries, requiring accurate address, telephone, and opening hours information. Event schema enables event-specific rich results with dates, venues, and ticket information, appearing prominently in both search results and Google Events search.

Understanding Rich Results

Rich results represent a significant competitive advantage in search. Studies consistently show that rich results achieve 58% higher click-through rates compared to standard listings. The visual enhancements draw the eye and provide users with immediate answers or information that helps them decide whether to click. Different schema types trigger different rich result formats.

FAQ rich results display expandable question-answer pairs directly beneath your search listing. Each question can be clicked to reveal its answer without leaving the SERP. This is particularly valuable because it dramatically increases your listing's visual footprint, pushing competitor results further down the page. HowTo rich results display numbered steps with optional images, providing a visual guide directly in search results. Recipe rich results show cooking time, calorie count, ratings, and an image thumbnail.

Not all structured data guarantees rich results. Google applies a quality evaluation process and may choose not to display rich results even when valid markup is present. Factors that influence rich result eligibility include the overall quality and trustworthiness of the page, compliance with Google's structured data guidelines, and whether the markup accurately represents the visible page content. Marking up content that is not visible to users (hidden structured data) violates Google's guidelines and can result in manual actions.

Implementation Best Practices

Successful structured data implementation requires attention to accuracy, completeness, and ongoing maintenance. The most important principle is that structured data must accurately represent the visible content on the page. Every property in your JSON-LD should correspond to information that users can see and verify on the page itself. Fabricating or exaggerating data (like inflating review counts or inventing author credentials) violates Google's guidelines.

Always include all required properties for your chosen schema type. Missing required fields will not cause errors but will prevent rich result eligibility. Use Google's Rich Results Test to verify your markup before deployment. This tool shows exactly which rich results your page is eligible for and identifies any errors or warnings. Run the test after every significant change to your structured data.

For sites with many pages, consider automating structured data generation through your content management system or templating engine. This ensures consistency across pages and reduces the risk of manual errors. When your content changes, the structured data should update automatically. Regular audits using Google Search Console's Enhancement reports help identify pages where structured data has become invalid or lost rich result eligibility due to content changes.

Frequently Asked Questions

What is schema markup?

Schema markup is structured data vocabulary from schema.org that helps search engines understand your content. It uses a standardized format to declare what entities exist on your page, their properties, and their relationships. When properly implemented, schema markup enables rich results in search that can significantly improve your click-through rates.

What is the difference between JSON-LD, Microdata, and RDFa?

JSON-LD uses a separate script tag and is Google's recommended format because it separates structured data from HTML markup. Microdata weaves attributes directly into HTML tags, making maintenance harder. RDFa also uses HTML attributes but follows the RDF specification. For SEO purposes, JSON-LD is the clear choice.

Which schema types does Google support for rich results?

Google supports over 30 schema types for rich results including Article, FAQ, HowTo, Product, LocalBusiness, Event, Recipe, Organization, BreadcrumbList, SoftwareApplication, Review, Video, Course, and JobPosting among others. Each type triggers a specific rich result format.

Where should I place JSON-LD in my HTML?

JSON-LD can be placed anywhere in the HTML document. Google recommends the head section for consistency, but the markup will be processed regardless of its position. You can include multiple JSON-LD script blocks on a single page for different schema types.

How do I test my schema markup?

Use Google's Rich Results Test at search.google.com/test/rich-results to validate your markup and see which rich results are eligible. The Schema.org Validator at validator.schema.org is also useful for general validation against the full schema.org specification.

Can I have multiple schema types on one page?

Yes, you can and should include multiple JSON-LD blocks on a single page when appropriate. For example, a recipe page might include Recipe, BreadcrumbList, and Organization schema. Each type should be in its own script block or combined using an @graph array.

Does schema markup directly improve rankings?

Schema markup is not a confirmed direct ranking factor. However, it enables rich results that consistently achieve higher click-through rates, and improved CTR can indirectly benefit rankings through user engagement signals. More importantly, structured data helps search engines understand your content better, which can improve relevance matching.

External resources: Schema.org | Google Structured Data Documentation