toolready. YAML ↔ JSON Converter

YAML ↔ JSON Converter

YAML ↔ JSON, both directions, with inline validation.

What this does

Converts between YAML and JSON. Both formats describe the same kind of data — nested maps, lists, and scalars — but YAML is friendlier for humans (indentation, no quotes on simple strings) and JSON is friendlier for machines (strict syntax, universally supported).

Watch out for

  • Numbers and strings. Bare YAML 1.10 becomes the number 1.1 — leading/trailing zeros are lost. Quote it ("1.10") to keep it a string. Especially relevant for version numbers.
  • Norway problem. no, yes, on, off are booleans in YAML 1.1. NO as a country code becomes false. js-yaml uses YAML 1.2 by default, where only true/false are booleans — but if you're round-tripping to an older parser, quote ambiguous strings.
  • Anchors and aliases. YAML &name / *name reference reuse expands into duplicated structures in JSON.
  • Comments. JSON doesn't support them; YAML # comments are dropped on the YAML → JSON pass.

Privacy

Parsing and serialization happen entirely in your browser via js-yaml. Nothing is uploaded.