JSONFormatter.org - Online JSON Formatter and JSON Validator will format JSON data, and helps to validate, convert JSON to XML, JSON to CSV. Save and Share JSON
JSON Editor Online - View, edit and format JSON online
DevToys - A collection of converters, formaters, encoders, generators and other tools for your Windows desktop.
ConvertOnline.IO - Free online tools to convert between various data formats including Javascript, YAML, JSON, HTTP Query String and more. Friendly online tools for URL decoding and encoding
JSONLint - JSON Lint is a web based validator and reformatter for JSON, a lightweight data-interchange format.
JSONMate - JSON tree editor, inspector and beautifier