SEO Schema Markup

SEO Schema Markup is a 100% free, open-source toolkit for creating and validating JSON-LD structured data. Fill in a simple form and get valid schema.org markup in real time, with required fields flagged in red and recommended fields in amber, so your output passes Google's Rich Results Test before you paste it into your site. Already have markup? Paste your JSON-LD or raw HTML into the validator and see exactly which properties are missing. Everything runs in your browser, and there is no signup and no data collection. It is built by WebSensePro and released under the MIT license.