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TOML ↔ JSON Converter

Convert between TOML and JSON in both directions with a live preview and clear error messages. Ideal for config files — runs entirely in your browser, so your data never leaves your device.

How to use TOML ↔ JSON Converter

  1. Pick a direction: TOML → JSON or JSON → TOML.
  2. Paste your source on the left.
  3. Copy the converted output, or use Swap to round-trip.

Frequently asked questions

Are comments preserved?
No — JSON has no concept of comments, so they cannot survive the round-trip. Keys, values, tables, and arrays all convert faithfully.
Is my data uploaded anywhere?
No. Parsing and serialization run locally in your browser via the smol-toml library.

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