CSV to JSON Converter
About the CSV ⇄ JSON Data Modeler
Convert tabular data between CSV and JSON in both directions. It is handy for turning a spreadsheet export into an API-ready array of objects, or flattening a JSON response back into a CSV you can open in Excel. Parsing happens locally in your browser, so your datasets are never uploaded to any server.
This tool works in your browser: the files and text you use are processed on your device and are not uploaded.
How to use it
- Paste CSV or JSON, or load a file.
- Choose the direction of conversion.
- Copy or download the converted output.
Frequently asked questions
How is CSV mapped to JSON?
The first CSV row is treated as the header, and each following row becomes a JSON object whose keys are those column names. The result is an array of objects — the shape most APIs and databases expect.
What happens to nested JSON when converting to CSV?
CSV is flat by nature, so deeply nested objects or arrays cannot map cleanly to columns. Flatten or stringify nested fields first; otherwise nested values may be serialised as text within a single cell.
How are commas and quotes inside values handled?
Standard CSV rules apply: values containing commas, quotes, or line breaks are wrapped in double quotes, and embedded quotes are doubled. This keeps fields from splitting incorrectly on import.
Is my data uploaded anywhere?
No. The conversion runs entirely in your browser, so sensitive spreadsheets and exports never leave your device.