Data tool
Convert pasted JSON to YAML, or YAML to formatted JSON. Everything runs in your browser.
Input
Output
Convert a JSON API example into readable YAML for documentation, or turn a small YAML configuration into formatted JSON for a tool that only accepts JSON. After conversion, compare booleans, numbers, nulls, arrays, and nested mappings rather than checking indentation alone. The output is a new serialization of the parsed data, not a text-preserving rewrite.
Invalid input leaves the result blank and places a parser message beside the controls, including line and column when the YAML parser provides them. JSON mode rejects comments and trailing commas. YAML mode can parse richer syntax than JSON, but the result still has to fit JSON-compatible data before it can be serialized usefully.
Comments, anchors, aliases, tags, quoting style, and original key spacing are presentation features that may be resolved or lost during a round trip. The tool does not validate an application schema or promise byte-for-byte reversibility. It handles pasted text only, so keep the original file and use a project-aware formatter for production configuration changes.
Parsing and serialization run locally in this browser tab. The page does not upload, store, or send pasted JSON or YAML to a server. Treat the converted result as sensitive when the source contains credentials or internal configuration, and verify the destination's policy before copying it elsewhere.