YAML to JSON

About YAML to JSON

YAML to JSON converts YAML configuration into JSON for APIs, JavaScript code and tools that only read JSON. It supports anchors, aliases and merge keys (<<), and multiple documents separated by ---.

It follows YAML 1.2 rules, so words like yes, no, on and off stay text instead of becoming booleans. Invalid YAML is reported with its line number. It runs entirely in your browser, so nothing you paste is uploaded.

Example

A GitHub Actions snippet. With YAML 1.2 rules the key "on" stays text instead of becoming true.

name: build
on: [push]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - run: npm test

{
  "name": "build",
  "on": [
    "push"
  ],
  "jobs": {
    "test": {
      "runs-on": "ubuntu-latest",
      "steps": [
        {
          "run": "npm test"
        }
      ]
    }
  }
}

When to use YAML to JSON

• Using YAML configuration in a tool or API that only reads JSON.
• Checking what a YAML file really contains after anchors and merges are applied.
• Converting OpenAPI or CI files for scripts.

Tips and common problems

• Tabs are not allowed for indentation in YAML — replace them with spaces.
• Several documents separated by --- become one JSON array.
• Comments are dropped because JSON has no comments.

Frequently asked questions

Guides

• JSON vs XML vs YAML — JSON vs XML vs YAML compared: strengths, weaknesses and best uses, to help you choose the right data format for APIs, config files and documents.