Three formats, one recommendation
Google reads three formats: JSON-LD, Microdata and RDFa. It recommends JSON-LD, a script block kept separate from the visible content, because it is the easiest to add and maintain. All three work equally well when valid. The vocabulary almost always comes from schema.org, a shared reference backed by the major search engines that defines types (Product, LocalBusiness, Event) and their properties.
What structured data delivers
It makes pages eligible for rich results: review stars, price and availability, breadcrumbs, event dates. Google cites publisher case studies: Rotten Tomatoes measured a 25% higher click-through rate on 100,000 marked-up pages, and Nestlé an 82% higher click-through rate on pages shown as rich results.
Eligibility requires every mandatory property and compliance with the guidelines. Google also retires features over time: it stopped showing FAQ rich results in 2026.
The most useful types for a small business
- LocalBusiness or a precise subtype (Plumber, Dentist, Restaurant): name, address, phone, hours, service area.
- Organization: logo, contact details and official profiles via the sameAs property.
- Product with Offer and AggregateRating for e-commerce.
- BreadcrumbList to display the page path.
- Article and Event for editorial content and dates.
Testing and monitoring
Validate each template with Google's Rich Results Test and the Schema Markup Validator, then watch the enhancement reports in Search Console, which list errors and warnings by type. One firm rule: markup must describe visible content. Claiming a 4.9 rating that appears nowhere on the page can lead to a manual action.
Roll markup out through templates rather than page by page, so one fix to the product template updates thousands of pages. Recheck after every CMS, plugin or theme update, since those often strip or duplicate JSON-LD blocks without warning.