TOML to JSON

TOML is the highly readable configuration format behind tools like Rust's Cargo (Cargo.toml), Python's pyproject.toml and many others. JSON, by contrast, is the format that APIs, scripts and web apps consume directly. This tool parses your TOML into an equivalent JSON object.

The conversion runs entirely locally in your browser (smol-toml, pure JavaScript). TOML tables become nested objects, arrays of tables become arrays, and date/time values become ISO strings. Very large integers beyond the safe JavaScript range are rejected with a clear message instead of being converted with precision loss. Invalid TOML is rejected with a clear error, and nothing is uploaded.

You will meet this when evaluating a Cargo.toml or pyproject.toml, loading a config into a script, or passing TOML settings to a frontend. TOML relies on sections in square brackets and plain key-equals-value lines, which keeps config files pleasant for humans to maintain; on conversion that structure survives as nesting in the JSON. The result is indented, readable JSON - ready to use right away.

Specifications

In 3 steps

1. Drop or pick your TOML file.
2. The tool parses it into JSON.
3. Download the JSON file.

Limitations: Supports TOML 1.0: tables, arrays of tables, inline tables, all scalar types and date/time values. Tables become objects, arrays of tables become arrays, date/time values become ISO strings; very large integers beyond the safe JavaScript range are rejected with a clear message (no lossy conversion). TOML comments (#) are lost, because JSON has no comments. Invalid TOML is rejected with a clear error.

FAQ

Related tools

YAML to JSON · JSON to XML · XML to JSON · JSON to TOML · YAML to TOML · TOML to YAML