JSON to YAML Converter & Validator - Online Tool

JSON Toolkit (Format/Validate ↔ YAML/TOML)

Format & validate JSON, convert between JSON ↔ YAML/TOML – or let Auto Detect do the work. Just paste, run, copy.

Tip: Cmd/Ctrl + Enter starts processing. Auto mode detects the format – or converts plain text into a JSON string.

Quick explanation

Auto detect tries JSON (Pretty-Print) → YAML → JSON → TOML → JSON in sequence. If nothing matches, the content is emitted losslessly as a JSON string (useful for safe embedding in JSON).

The YAML/TOML parsers are intentionally minimal (everyday subset): YAML supports key:value, indentation, lists (- item), scalar values. TOML supports keys/dotted keys, [tables], [[array tables]], arrays, strings/numbers/booleans (datetime as string).