About this tool
JSON, CSV and YAML are the three data formats you meet most often: JSON is the lingua franca of APIs and frontends, CSV carries tabular data for Excel and spreadsheets, and YAML is the format of choice for config files (Kubernetes, CI, Docker Compose). This tool converts freely between them — turn an API’s JSON response into CSV for Excel, or rewrite a config from JSON into more readable YAML.
Conversion runs locally in your browser (YAML handling uses js-yaml) and nothing is uploaded, so it is safe for configs or business data with internal information. Keep the formats’ capabilities in mind: JSON/YAML are nested tree structures while CSV is a flat 2-D table — converting deeply nested JSON to CSV requires flattening or serializing nested fields, which is a limitation of the format itself, not the tool.
How to use
- Paste your source data (JSON, CSV or YAML) into the input pane.
- Pick the source and target formats, e.g. JSON → YAML.
- The tool first validates the source, then converts; if there is a syntax error it points out where.
- Review the result in the output pane and verify the structure and fields.
- Copy the result with one click, or download it as a file in the target format.
When to use it
- Turn an API’s JSON array into CSV for analysis in Excel or Google Sheets.
- Rewrite a hand-written JSON config into more readable, comment-friendly YAML (e.g. a K8s manifest).
- Convert a CSV list from a colleague into JSON so a program can read it.
- Migrate project settings between YAML and JSON configs.
- Quickly check whether a snippet of YAML/JSON is valid — a failed conversion means the syntax is off.
FAQ
Can deeply nested JSON convert to CSV?
CSV is a flat 2-D table and cannot natively express arbitrary nesting. An array of uniform objects maps to CSV cleanly, but deeply nested fields must be flattened into column names like `a.b.c` or serialized to strings. For complex structures, converting between JSON and YAML is more lossless.
Does YAML-to-JSON lose comments?
Yes. The JSON standard has no comments, so `#` comments in YAML are dropped when converting to JSON. The reverse direction (JSON → YAML) has no comments to lose. If comments matter, add them back manually after converting.
How are CSV delimiters and headers handled?
The usual convention is comma-separated with the first row as field names (a header); when converting to JSON, each row becomes an object keyed by the header. Cells containing commas or newlines must be quoted, per the CSV spec. Make sure your CSV has a header row with clean field names before converting.
Is the data uploaded to a server?
No. All conversion happens locally in your browser; the data never leaves your device, making it safe for internal configs or business data.