Validate before conversion
Malformed JSON or YAML produces a readable parser error instead of partial output.
Developer Tools · Local processing
JSON ↔ YAML Converter
Convert JSON to YAML or YAML to formatted JSON with safe local parsing.
Safe local parser
JSON ↔ YAML Converter
Inputs and results stay in this page and are not sent to any server.
Converted output
The practical guide
Translate structured data while preserving ordinary scalar and collection types.
The converter parses data rather than executing it, then serializes the resulting arrays, objects, strings, numbers, booleans, and null values into the other format.
Data types and formatting
Maps and sequences become objects and arrays. YAML features without a direct JSON representation may be normalized during conversion.
No arbitrary object execution
The standards-based parser is used for data conversion; input is not evaluated as JavaScript or loaded as executable application configuration.
Privacy by architecture
Your files and tool inputs stay in your browser.
The selected files, inputs, settings, and outputs are processed in this page and are not uploaded to any server.
Questions, answered
Frequently asked questions
Can YAML comments survive conversion to JSON and back?
No. JSON has no comments, so comments and some formatting details are not preserved.
Are YAML anchors preserved?
They may be resolved into ordinary data during parsing rather than retained as source-level anchor syntax.
Can I convert top-level arrays?
Yes. Both JSON arrays and YAML sequences are supported.
Is the input uploaded?
No. Parsing and serialization happen in this browser.