YAML to JSON Converter

Paste YAML or drop a .yml file onto the input and the JSON appears alongside it. The converter understands the parts of YAML that plain JSON cannot express and resolves them for you: anchors and aliases (&base and *base) are expanded, merge keys (<<: *base) are merged into the parent mapping, and comments are dropped because JSON has no place for them.

A file that contains several documents separated by ---, as Kubernetes manifests often do, is converted into a JSON array with one element per document. A single document stays a single value. Choose two spaces, four spaces or a minified result.

If the YAML is invalid you will see the first problem with its line and column, such as a tab used for indentation, inconsistent indent levels or a duplicate key. Fix it and the output updates as you type.

YAML input:

defaults: &defaults
  retries: 3
  timeout: 30
service:
  <<: *defaults
  timeout: 60
  ports: [80, 443]

JSON output:

{
  "defaults": { "retries": 3, "timeout": 30 },
  "service": { "retries": 3, "timeout": 60, "ports": [80, 443] }
}

The service block inherited retries from the anchor and overrode timeout, exactly as a YAML consumer would see it.

• Unquoted values are typed: port: 80 is a number, debug: false a boolean and owner: null or owner: ~ null. Quote a value to force a string.
• YAML 1.2 rules: yes, no, on and off are plain strings, not booleans as in YAML 1.1.
• Dates: timestamps such as 2025-01-15 are kept as strings in the JSON.
• To produce YAML from JSON, use the JSON to YAML converter.