JSON to .env converter
Useful for Docker, Node.js and ASP.NET when moving JSON settings into environment variables. The __ separator is what ASP.NET Core uses for levels.
Loading the tool…
Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter json text, level separator and upper_case names.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Key paths are joined with the chosen separator, so database.host becomes DATABASE__HOST and list items become LIST__0. Any character other than Latin letters, digits and _ becomes _. Simple values are written as they are, values with spaces or symbols go in single quotes, and values with line breaks go in double quotes with \n.
Example
Inputs: Level separator = Double underscore __, UPPER_CASE names = yes. Result: .env: APP=toolsahla VERSION=2.1.0 PORT=8080 DEBUG=false LANGUAGES__0=ar LANGUAGES__1=en DATABASE__HOST=localhost DATABASE__USER=admin DATABASE__TIMEOUT=30 ; Variables: 9.
{
"app": "toolsahla",
"version": "2.1.0",
"port": 8080,
"debug": false,
"languages": ["ar", "en"],
"database": {
"host": "localhost",
"user": "admin",
"timeout": 30
}
}APP=toolsahla VERSION=2.1.0 PORT=8080 DEBUG=false LANGUAGES__0=ar LANGUAGES__1=en DATABASE__HOST=localhost DATABASE__USER=admin DATABASE__TIMEOUT=30
Limits and caveats
- Every value becomes text, since environment variables are text.
- Some tools such as Docker Compose expand $ inside double quotes, so check values that contain $.
Questions about this tool
When should I pick __ over _?
Pick __ when keys already contain _, so levels stay distinct from names. It is also the ASP.NET Core convention.
Why do I get "both become" errors?
Two keys such as a-b and a_b both turn into A_B. Rename one of them in the JSON.
How is null written?
As an empty value such as KEY=, since environment variables have no null.