File & Format Converters · Free tool

YAML ↔ JSON Converter

Convert YAML to JSON or JSON to YAML. Paste on one side, copy the other. Works for config files, data docs, and more.

Updated April 2026

YAML input

JSON output

{
  "name": "freetoolarena",
  "stack": [
    "next.js",
    "tailwind"
  ],
  "published": true,
  "pages": 165
}

Supports scalars, nested mappings, and sequences with block (-) or flow ([ ], { }) syntax. Tabs are not valid indentation in YAML.

What it does

A free two-way YAML ↔ JSON converter. Paste YAML to get JSON, or paste JSON to get clean YAML — then hit Swap to bounce in the other direction with the output promoted to the new input. Supports nested mappings, block and flow sequences, strings, numbers, booleans, and null.

YAML is the config-file default for Kubernetes, GitHub Actions, Docker Compose, Ansible, and most dev tooling. JSON is the default for APIs and JavaScript. Translating between them is an everyday task. Tip: YAML disallows tab characters in indentation — if a paste errors, check for mixed tabs and spaces.

How to use it

Pick the direction you want: YAML → JSON or JSON → YAML.
Paste or type in the top box.
Read the output instantly in the bottom box — errors show inline.
Hit Swap to flip direction and continue iterating.