You have probably seen Google results with star ratings, FAQ drop-downs, recipe cooking times or event dates shown right on the page. Those rich results come from structured data, and the format Google prefers is called JSON-LD. It sounds technical, but the idea is simple.
What structured data is
A web page is written for humans. Structured data is a small, separate description of the page written for machines, that says plainly: this is an article, by this author, published on this date; or this is a product, costing this much, with this rating. Search engines read it to understand the page properly rather than guessing from the text.
Why JSON-LD specifically
There are a few ways to add structured data, but JSON-LD is the one Google recommends. It sits in a small script block and is kept separate from your visible HTML, so it does not get tangled up with your layout. You can add or change it without touching the design.
What you can mark up
- Article and BlogPosting: author, date, headline.
- Product: price, availability, rating.
- FAQ: questions and answers that can show directly in results.
- LocalBusiness: address, opening hours, phone.
- Recipe, Event, HowTo, Organization, Person and more.
Does it help SEO?
It does not directly boost your ranking, but it makes you eligible for rich results, which are bigger, more eye-catching and tend to get clicked more. It also helps search engines and AI tools understand and cite your content correctly. Incomplete or broken markup, on the other hand, can stop those rich results appearing at all.
Add it without hand-writing it
Writing JSON-LD by hand is fiddly and easy to get wrong. The JSON-LD schema generator lets you fill in a form and gives you valid, ready-to-paste markup for the common types. Once it is on your page, run the page through the schema markup checker to confirm Google sees every required field. Generate, paste, verify, done.