Why convert YAML to JSON?

YAML is great for human-edited configuration, while JSON is the standard for APIs, data interchange and programmatic processing. Converting YAML to JSON lets you feed config files to APIs, validate them against a schema, or inspect their exact structure.

Example conversion

YAML

server:
  host: localhost
  port: 8080
database:
  name: app
  replicas:
    - db1
    - db2

JSON

{
  "server": { "host": "localhost", "port": 8080 },
  "database": {
    "name": "app",
    "replicas": ["db1", "db2"]
  }
}

Supported YAML features

YAML	JSON result
Mappings (`key: value`)	Objects
Sequences (`- item`)	Arrays
Inline arrays (`[a, b]`)	Arrays
Multi-line strings (`\|` and `>`)	Strings with line breaks
`true` / `false`	Booleans
`null` / `~`	`null`
Anchors and aliases (`&a` / `*a`)	Expanded values

Common use cases

API integration — send a YAML config as a JSON request body
Kubernetes debugging — see the exact structure of a manifest
Config validation against a JSON Schema
Data processing in languages with built-in JSON support
Generating JSON examples for documentation

YAML gotchas

The Norway problem: in YAML 1.1 values like NO and YES are read as booleans. Quote them if you mean text.
Numbers: 1.0 becomes the number 1, not the string "1.0"; a zip code such as 01234 may be read as octal. Quote ambiguous values.

Programmatic conversion

// Node.js (js-yaml)
const yaml = require('js-yaml');
console.log(JSON.stringify(yaml.load(text), null, 2));

# Python (PyYAML)
import json, yaml
print(json.dumps(yaml.safe_load(text), indent=2))

# Command line (yq)
yq -o=json file.yaml

Pro tips

YAML is whitespace-sensitive — check your indentation if parsing fails.
JSON doesn't support comments, so YAML comments are dropped.
Run the result through a JSON validator to double-check it.

YAML to JSON Converter