The Schema Builder for Structured Data is a free Chrome extension that allows users to easily generate validated JSON-LD structured data markup for any webpage. With over 20 supported schema types, including Google's recommended markups, users can simply enable the plugin, choose the desired schema markup, and populate the form using point-and-click or manual input. The extension also includes a built-in schema testing tool to validate existing markup and identify errors or warnings. Available in English and Japanese, this user-friendly extension streamlines the process of generating structured data markup, making it accessible to all.