Structured Data tools help you generate structured data markup in JSON-LD, RDFa, Microdata, etc., debug and validate Schema.org structured data, and more.
Mr. Free Tools’ Filters
Open Source: an open-source tool is often completely free, but some exceptions are offered as a freemium.
Free Tool: a tool offered for free in its full version with all features and no limitations.
Freemium Tool: a tool offered for free with some limitations (limited features, limited support, limited usage, etc.).
Free to Try: the full version of the tool for a brief period to test it before purchase (Free trial).
Free Micro Tool: a free simple tool that performs a basic and specific task. For example, a meme generator or word counter.
Free Resource: these could be free courses, graphic assets, templates, directories, or anything else free and useful.
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