JSON to ENV Converter

How to use the json to env converter

1. Paste a valid JSON object into the JSON input text area.
2. Optionally add a key prefix such as APP_ to namespace every variable.
3. Choose a nested key separator: single or double underscore.
4. The output updates live. Copy the generated lines directly into your .env file.

How the conversion works

The converter parses the input with JSON.parse and walks the resulting object tree. For each leaf value it builds a key by joining ancestor property names with the chosen separator, converting everything to uppercase. The value is then stringified and wrapped in double quotes.

Consider this input: {"database":{"host":"localhost","port":5432}}. The walker visits database.host and database.port, producing DATABASE_HOST="localhost" and DATABASE_PORT="5432".

Keys are sorted alphabetically at every level so the output order is deterministic regardless of how the original JSON was formatted.

Handling special values

Environment variables are always strings, so non-string types need conversion. Numbers become their decimal representation. Booleans become the literal words true or false. A JSON null becomes an empty string between the quotes.

Arrays and deeply nested objects that you do not want flattened can be kept as JSON strings. When the walker encounters an array, it serializes the entire array with JSON.stringify and places the result inside quotes. This means your application code will need to parse that value back from JSON at runtime.

Unicode characters are preserved exactly as they appear. If your JSON contains an emoji, the output line will contain the actual emoji character inside the quotes.

Escaping rules

Because every value is enclosed in double quotes, certain characters inside the value must be escaped so that parsers read them correctly. The converter applies these escape sequences:

This matches the escaping behaviour expected by popular libraries such as dotenv for Node.js and Python's python-dotenv.

Common mistakes to avoid

A frequent error when performing a json to env conversion is pasting a JSON array instead of an object. The root value must be an object because environment variables require named keys. If you have an array, wrap it in an object first, for example {"ITEMS":[...]}.

Another issue is forgetting that key names are uppercased automatically. If your downstream system expects mixed-case variable names, you will need to adjust the output manually. Most operating systems treat environment variable names as case-sensitive on Linux and macOS but case-insensitive on Windows, so uppercase is the safest convention.

If you need to transform JSON into other structured formats rather than flat variables, tools like json to xml or json to sql may be more appropriate.

Using the output in your project

Copy the generated lines into a file named .env at the root of your project. Make sure this file is listed in your .gitignore so secrets are not committed to version control.

In Node.js, install the dotenv package and call require('dotenv').config() at the entry point of your application. In Python, use python-dotenv and call load_dotenv(). Docker Compose reads .env files automatically when you use the env_file directive.

For generating language-specific type definitions from the same JSON source, see sibling converters such as json to go struct, json to c# class, json to java class, or json to python class.

Worked examples