How to Convert JSON to YAML (and Back)

March 22, 2026 · 5 min read

JSON and YAML are two of the most popular data serialization formats. If you work with configuration files, APIs, or DevOps tools, you'll inevitably need to convert between them.

In this guide, you'll learn the key differences between JSON and YAML, when to use each, and how to convert between them — with examples and a free online converter.

JSON vs YAML: Key Differences

Feature	JSON	YAML
Syntax	Braces and brackets	Indentation-based
Comments	Not supported	Supported (#)
Readability	Good for machines	Great for humans
Data types	Strings, numbers, booleans, null, arrays, objects	Same + dates, timestamps, multi-line strings
Common use	APIs, package.json, tsconfig	Docker Compose, Kubernetes, Ansible, CI/CD
Strictness	Very strict (quotes required)	More flexible (quotes optional)

The Same Data in JSON and YAML

JSON

{
  "name": "my-app",
  "version": "1.0.0",
  "dependencies": {
    "express": "^4.18.0",
    "lodash": "^4.17.21"
  },
  "scripts": {
    "start": "node index.js",
    "test": "jest"
  },
  "production": true,
  "ports": [3000, 8080]
}

YAML

name: my-app
version: 1.0.0
dependencies:
  express: ^4.18.0
  lodash: ^4.17.21
scripts:
  start: node index.js
  test: jest
production: true
ports:
  - 3000
  - 8080

The YAML version is shorter and arguably easier to scan. This is why YAML is the go-to format for configuration files like docker-compose.yml, .github/workflows/*.yml, and Kubernetes manifests.

How to Convert JSON to YAML

Method 1: Online Converter (Instant)

The fastest way — paste your JSON and get YAML instantly:

Convert JSON to YAML

Paste JSON, get clean YAML. Runs in your browser — nothing leaves your device.

Open JSON to YAML Converter

Method 2: Command Line with Python

# Install PyYAML if needed
pip install pyyaml

# Convert a file
python -c "import json, yaml, sys; print(yaml.dump(json.load(sys.stdin), default_flow_style=False))" < config.json > config.yaml

Method 3: Command Line with yq

# Install yq (https://github.com/mikefarah/yq)
# macOS: brew install yq
# Linux: snap install yq

# Convert JSON to YAML
yq -P config.json > config.yaml

# Convert YAML to JSON
yq -o=json config.yaml > config.json

Method 4: In Node.js

const fs = require('fs');
const yaml = require('js-yaml');  // npm install js-yaml

// JSON to YAML
const jsonData = JSON.parse(fs.readFileSync('config.json', 'utf8'));
const yamlStr = yaml.dump(jsonData);
fs.writeFileSync('config.yaml', yamlStr);

// YAML to JSON
const yamlData = yaml.load(fs.readFileSync('config.yaml', 'utf8'));
const jsonStr = JSON.stringify(yamlData, null, 2);
fs.writeFileSync('config.json', jsonStr);

How to Convert YAML to JSON

Going the other direction? Use the YAML to JSON converter or the command-line methods above in reverse.

Convert YAML to JSON

Paste YAML, get formatted JSON.

Open YAML to JSON Converter

Common Gotchas

YAML indentation matters — use spaces, never tabs. Most tools use 2-space indentation.
Unquoted strings can be tricky — yes, no, true, false, and null are interpreted as booleans/null in YAML, not strings. Quote them if you mean the literal string.
Multi-line strings — YAML supports | (literal block) and > (folded) for multi-line strings. JSON requires \n escapes.
Comments are lost — when converting YAML to JSON, all comments (#) are stripped since JSON doesn't support them.

When to Use Which

Use JSON for APIs, data interchange, and any context where strict parsing is important (package.json, tsconfig.json)
Use YAML for configuration files that humans read and edit frequently (Docker Compose, Kubernetes, GitHub Actions, Ansible)

Related Tools

JSON to YAML Converter
YAML to JSON Converter
JSON Formatter — pretty-print and validate JSON
JSON Validator — check if your JSON is valid before converting