JSON to Properties Explained: Flattening Nested Settings
Properties files are flat, while JSON is nested. This guide explains how dotted keys and indexed items bridge the two formats.
What is the JSON to Properties Converter?
Java properties files store settings as flat key=value lines, while JSON often nests settings inside objects. This tool flattens a JSON object so nested keys become dotted paths, such as app.name, and array items gain an index in brackets. The input must be a JSON object; a top-level array or plain value is rejected with a message. Values are written as they appear, without quoting, which matches properties style but means values containing special characters may need care in a real properties file.
How to use it
- Paste a JSON object into the box.
- Press Convert to properties.
- Copy the key=value lines into your properties file.
Worked example
The sample converts to three lines: app.name=Demo, app.port=8080 and debug=true.
How do I write a nested JSON setting as a property?
Join the keys with dots. For example, app containing name Demo becomes app.name=Demo.
Frequently asked questions
How are nested objects handled?
Nested keys are joined with dots, so an object inside app called name becomes app.name.
What happens to arrays?
Array items get their index in brackets, so the first item of a list called servers becomes servers[0].