Question 1

What is YAML?

Accepted Answer

YAML (YAML Ain't Markup Language) is a human-readable data serialization format commonly used for configuration files. It uses indentation and minimal punctuation, making it easier to read and write than JSON for complex nested data.

Question 2

When should I use YAML vs JSON?

Accepted Answer

Use YAML for configuration files (Docker Compose, Kubernetes, CI/CD pipelines) where human readability matters. Use JSON for APIs, data interchange, and JavaScript applications where machine parsing speed and universal support are priorities. JSON is a strict subset of most parsers; YAML is a superset of JSON.

Question 3

Does this converter support multi-document YAML?

Accepted Answer

This tool converts single-document YAML. Multi-document YAML files (using --- separators) are not supported — only the first document would be parsed. Split multi-document files before converting.

Question 4

Why does my YAML output look different from the input?

Accepted Answer

When converting JSON to YAML, the output is normalized: keys are sorted alphabetically, strings are quoted only when necessary, and numbers/booleans are unquoted. The data is semantically identical even if the formatting differs from your original YAML.

Question 5

Is my data sent to a server?

Accepted Answer

No. All conversion happens entirely in your browser using the js-yaml library. No data is transmitted over the network at any point.

YAML ↔ JSON Converter

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