YAML to JSON

Paste YAML and get formatted JSON instantly. Runs in your browser — your data never leaves your device.

Runs in your browser Instant No signup, no tracking

About this tool

This tool converts YAML 1.2 documents into pretty-printed JSON. YAML is popular for configuration (Kubernetes, GitHub Actions, Docker Compose) because it's human-friendly, but most APIs and libraries expect JSON. Common gotchas: unquoted `yes`, `no`, `on`, `off` become booleans; large integers can lose precision; and multi-document streams (separated by `---`) are only partially represented in JSON — this converter reads the first document. All conversion happens in your browser using js-yaml, so pasted secrets and internal configs never leave your machine.

Example

Paste the input on the left and you will get output like this:

Sample YAML

server:
  host: localhost
  port: 8080
  ssl: true
  admins:
    - alice
    - bob

Resulting JSON

{
  "server": {
    "host": "localhost",
    "port": 8080,
    "ssl": true,
    "admins": [
      "alice",
      "bob"
    ]
  }
}

How to use YAML to JSON

  1. Paste or type your YAML into the left pane.
  2. The JSON appears instantly in the right pane. Conversion runs in your browser — nothing is uploaded.
  3. Copy the result to your clipboard or download it as a file.

FAQ

Does this handle multi-document YAML?
It converts the first document. To convert several, split them by --- and paste one at a time.
Are YAML anchors and aliases resolved?
Yes — anchors (&name) and aliases (*name) are dereferenced before JSON serialization.
Is my data sent to a server?
No. Parsing runs entirely in your browser. You can inspect the network tab to confirm.