Alternatives to JSON Viewer

Quicklook extension for source files

Scriptable JSON formatter and editor

Markdown previewer with bundled Quick Look extension

Text editor

Quick Look plugin to pretty-print JSON

Interactive tool for analyzing MongoDB data

All-in-one toolbox for developers

Code editor

Visualise all aspects of compiled Java class files and the contained bytecode

App for iOS view debugging

JavaScript playground that auto-evaluates as code is typed

Property list and JSON editor