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JSON to TOML

JSON → TOML · pyproject / Cargo / Hugo · null handling

Paste JSON, get TOML. Nested objects become tables ([parent.child]); arrays of objects become array-of-tables ([[items]]). Reverse direction at TOML → JSON. Note: TOML has no null — choose how to handle it.

Paste JSON.

How to convert JSON to TOML

  1. Paste in either panel.
  2. The opposite panel updates live. Swap to flip direction.
  3. TOML output respects the original key order. Nested objects become tables ([parent.child]); arrays of objects become array-of-tables ([[items]]).
  4. Copy or Download.

FAQ

Why does TOML drop my nulls?

TOML has no null value. The default behaviour is to drop null keys; the alternative is to substitute the literal string "null". Pick whichever your downstream tool tolerates.

What about mixed-type arrays?

TOML allows them (since 1.0). Older parsers may not — keep arrays homogeneous if you can.

Will it work offline?

Yes — uses @iarna/toml, cached after first load.