TOML is the config format of choice for Rust (Cargo.toml), Python (pyproject.toml), and Hugo — clear, minimal, and easy to read. This tool converts between JSON and TOML in both directions, useful when you need to migrate configs or generate TOML programmatically from JSON data.

Converting JSON to TOML is handy when you're scaffolding a new project and have your config data in JSON form — maybe from an API, a template engine, or a script. The converter maps JSON objects to TOML tables, arrays to TOML arrays, and handles nested structures cleanly.

Going from TOML to JSON is useful when you need to process config files programmatically. Most languages have better JSON support than TOML support, so converting to JSON first can simplify parsing and manipulation. All processing happens in your browser — nothing is sent to any server.

Tips

TOML distinguishes between inline tables and standard tables — the converter uses standard tables for readability.
TOML has native date/time types. If your JSON has ISO 8601 date strings, they'll convert to TOML datetime values.
Nested objects in JSON become dotted key sections in TOML (e.g., [database.connection]).
TOML arrays of tables use [[array_name]] syntax — check the output carefully when converting complex nested arrays.