YAML to JSON Converter — Convert YAML to JSON Online Free

YAML supports single-line comments starting with #, but JSON has no comment syntax. When converting YAML to JSON, all comments are stripped from the output. If you need to preserve annotation data, move it into a dedicated JSON field such as "_comment" before converting.

YAML anchors (&name) and aliases (*name) are dereferenced during conversion — each alias is replaced with a full copy of the anchored value. The resulting JSON contains no anchor or alias syntax, just the expanded data. This means a large anchor reused many times will produce repeated data in the JSON, which may increase file size.

YAML 1.1 recognized values like yes, no, on, off, and y/n as booleans, but YAML 1.2 (the current spec) only treats true and false as booleans. Parsers following YAML 1.1 (common in older Ruby and Python libraries) will convert yes to true in JSON, while YAML 1.2 parsers output "yes" as a string. Wrap ambiguous values in quotes in your YAML source to guarantee string output.

YAML literal block scalars (|) preserve newlines as \n in the JSON string value. Folded block scalars (>) collapse newlines into spaces, so each paragraph becomes a single space-separated line in JSON. The final newline behavior is controlled by the chomping indicator: - strips trailing newlines, + keeps them, and the default keeps exactly one.

A YAML file can contain multiple documents separated by --- (and optionally ended with ...). Standard JSON has no multi-document format, so most converters either output only the first document or produce a JSON array where each element is one document. Check your converter's behavior; this tool wraps multiple documents into a JSON array to keep all data accessible.