YAML to JSON Converter Online - Free & Private

Paste YAML or drop a .yml file and get formatted JSON. Comments are dropped, anchors and aliases are expanded, and a file with several documents becomes a JSON array. If the YAML is invalid, you see the line and column of the problem.

How to convert YAML to JSON

1. Paste YAML into the left editor, or open or drop a .yaml or .yml file.
2. Formatted JSON appears on the right. A YAML syntax error is marked in the editor with its line number and a short reason, such as bad indentation.
3. Browse the result in tree view, copy it, or download it as a .json file.

What happens to YAML features

• Comments are removed, because JSON has no comments.
• Anchors and aliases (&defaults and *defaults) and merge keys (<<: *defaults) are expanded into full copies of the values.
• Several documents separated by --- become a JSON array with one item per document, which is how a multi-resource Kubernetes file is usually shaped.
• Block scalars (| and >) become ordinary strings with their line breaks kept or folded as YAML defines.
• Types follow the YAML 1.2 core schema: true, false, numbers and null are typed values, and dates stay as strings.

When to use it

Converting YAML to JSON is useful when an API, a JSON Schema validator or a script expects JSON, when you want to check exactly how a YAML file is parsed (indentation mistakes become obvious in the tree view), or when you need to paste a config into a tool that only accepts JSON.

Example

defaults: &defaults
  retries: 3
api:
  <<: *defaults
  url: https://example.com

becomes {"defaults":{"retries":3},"api":{"retries":3,"url":"https://example.com"}}.

The JSON to YAML converter does the reverse.

Private by design

Your YAML is parsed in your browser with the open-source js-yaml library and is never uploaded.