JSON to YAML Converter

Convert JSON data to YAML format with proper indentation and comment support.

Tested tool guide Tested browser tools Checked August 16, 2026

What JSON to YAML Converter does, with a checked example

JSON to YAML Converter turns a valid JSON document into an equivalent YAML representation. It maps objects to mappings, arrays to sequences, and scalar values to YAML scalars, then formats nesting with YAML indentation. It is useful when a configuration or data sample is available in JSON but a YAML-consuming system is expected. The common surprise is comment handling: YAML permits comments, but standard JSON does not, so comments cannot be recovered from ordinary JSON input. Conversion runs in the browser; pasted data is not uploaded.

Worked example

A concrete input and expected output from the current implementation.

Input

{
  "count": 2
}

Expected output

count: 2

The single JSON object becomes a YAML mapping with one key. The JSON number 2 remains the numeric scalar 2; braces, quotes around the simple key, and comma syntax are unnecessary in YAML.

How the result is produced

Value mapping

The input must represent a JSON value. Object members become YAML mapping entries, arrays become sequences, and JSON strings, numbers, booleans, and null become corresponding YAML scalars. Nesting is expressed with indentation rather than JSON braces and brackets. The conversion changes syntax, not the logical tree of keys and values.

Comments and indentation

YAML indentation is structural, so nested output is aligned by level. YAML comments start with # outside quoted scalars. Valid JSON provides no comment syntax, so the converter cannot derive or preserve source comments from standards-compliant JSON. Comments added to YAML describe the document but are not values in the converted data.

Good uses

Convert a JSON deployment snippet into YAML before placing it in a system that accepts YAML configuration.
Translate an API response fixture from JSON into a YAML fixture while retaining nested objects, arrays, booleans, numbers, and null values.
Create a YAML starting point from exported JSON settings, then annotate the YAML with comments for maintainers.

Limits and checks

The converter changes representation only. It does not verify whether the resulting keys and values satisfy Kubernetes, CI, OpenAPI, or another application's schema.
Avoid duplicate object member names. JSON interoperability is unpredictable when names repeat, and a converted mapping may not retain every occurrence even if the original text is accepted.
Do not expect lexical details to survive. Whitespace, braces, commas, escape spelling, and unnecessary quotes can change, while comments and trailing commas are not part of standard JSON.

Common questions

Can it preserve comments from JSON?

No. RFC 8259 JSON has no comment syntax, so a standards-compliant JSON document supplies no comments to carry over. YAML supports comments, and they can be added to the YAML text, but they are annotations rather than values. Inputs using JSON5-style or JavaScript comments should not be assumed to be valid JSON for this converter.

Will converting the YAML back reproduce the original JSON exactly?

No. A YAML-to-JSON conversion can often recover the same JSON-compatible data tree, but it cannot restore original whitespace, key quoting, escape spelling, or member formatting. YAML comments are also discarded because JSON has no place for them. YAML-specific constructs such as aliases, tags, and non-string mapping keys may not have a direct JSON equivalent.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.