Convert CSV ↔ JSON ↔ TSV and preview / edit as a table. Custom delimiter, quote handling, header toggle.
Pick a mode. CSV → JSON uses the first row as object keys (toggle it off to get col1/col2/…). JSON → CSV takes an array of objects, unions all keys for the header and stringifies nested values. CSV ↔ TSV swaps the delimiter. Preview mode renders the data as an HTML table — click any cell to edit it, then click Convert again to re-emit. Auto-detect picks comma / semicolon / tab / pipe based on counts in the first non-empty line. Quoting: Always = RFC-4180 safe; Needed = only quote when the field contains the delimiter / quote / newline; Never = raw output. Everything stays in your browser.