There is a web based tool for generating JSON documents from JSON Schema documents at http://schematic-ipsum.herokuapp.com/ but I can't vouch for how well it works. It is included on the list of tools on the JSON Schema website.
The down vote is most likely because asking for tool recomendations is considered off-topic. If you phrased your question like "How can I do X? My requirements are Y", then you avoid such downvotes (hopefully).