YAML is easier to read and comment, which is why config files use it. JSON is easier to generate.

Developer Data

JSON to YAML

Input

{"name":"my-app","port":8080,"debug":false,"version":"1.0","tags":["web","api"]}

What to do

Indent

Output

name: my-app
port: 8080
debug: false
version: "1.0"
tags:
  - web
  - api

Processed in your browser · nothing is uploaded

Local · always lossless in this direction

Serialises JSON as YAML, quoting any string that would otherwise be read back as a different type — which is the part hand-conversion gets wrong.

How to use the json to yaml

1 Paste your input. The result appears immediately.

2 Pick the operation you want.

3 Copy the result, or save it as a file.

The quoting rules are the whole job. A JSON string `"1.0"` written to YAML unquoted comes back as the number 1, losing the trailing zero and changing the type — which matters enormously for a version number. The same applies to `"true"`, `"no"`, `"null"` and anything starting with a digit. This quotes all of them. Going in this direction is always safe, unlike parsing, because serialising has no ambiguity to resolve: there is exactly one correct YAML representation of any JSON value, and the only question is how much of it needs quotes.

Questions

Why are some of my strings quoted? −

Because they would be read back as a number, boolean or null otherwise. "1.0" unquoted becomes the number 1.

Is converting JSON to YAML lossless? +

Why convert at all? +

Does it preserve key order? +

Is my data sent anywhere? +

Sources

YAML 1.2 specification

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