Paste or upload data on the left. Everything converts locally - nothing is uploaded to a server.
Frequently asked questions
Can it convert nested JSON to CSV?
The converter works with flat structures: an array of objects becomes rows with the union of keys as columns, and an array of arrays maps directly. Nested objects or arrays inside a value are not flattened; they are stringified into the cell as JSON so no data is lost.
Why does my Excel CSV come out as one column?
Excel in many European locales exports CSV files separated by semicolons instead of commas, so a comma parser sees each line as a single field. Switch the delimiter select to semicolon (or tab for TSV exports) and the columns will split correctly, including quoted fields that contain the delimiter.
Is my data uploaded to a server?
No. Parsing and conversion run entirely in your browser with JavaScript; pasted text and uploaded files are read locally and never transmitted or logged. That makes it safe for customer exports, financial data, and other spreadsheets you would not want to paste into a random online converter.