TOML ↔ JSON

Client

Convert between TOML and JSON in your tab—paste on either side, format, and copy. A small JSON example is pre-filled so you can try JSON → TOML immediately.

Learn more: JSON and TOML

Switch between JSON and TOML when working with project manifests, tool configs, or languages that favor one format.

What TOML is

TOML (Tom’s Obvious, Minimal Language) is designed for config files: explicit tables, clear datetime and number literals, and fewer punctuation rules than JSON for many everyday files.

Interchange

Both JSON and TOML represent key–value data and nesting. Conversion is straightforward for typical configs; exotic TOML features may need a quick sanity check after conversion.

JSON & TOML

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JSON → TOML uses JSON.parse then a TOML serializer. Root JSON arrays are wrapped under a root key. TOML → JSON uses TOML.parse then JSON.stringify.

Dates and inline tables may differ slightly from your source editor—validate for production configs.

Sample JSON is pre-filled—click JSON → TOML to fill the right panel. Parsing runs in your browser.

Common use cases

  • Edit Rust, Python, or Node config files that use TOML while reasoning about the same data as JSON.
  • Share a JSON fixture with someone who prefers TOML for human-edited defaults.
  • Format either side after pasting minified or noisy config from a terminal.

Common mistakes to avoid

  • Assuming date and table rules match JSON exactly

    TOML has native dates and dotted keys. After conversion, spot-check values your runtime will parse.

FAQ

Are configs uploaded?

No. Conversion runs in your browser.

More tools

Related utilities you can open in another tab—mostly client-side.