CSV ⇄ JSON Converter
Spreadsheet data to JSON and back, in both directions.
Converting between CSV and JSON
Spreadsheets export CSV; APIs and databases speak JSON. This converter bridges them in both directions: paste CSV and get a JSON array of objects keyed by the header row, or paste a JSON array of flat objects and get CSV ready to open in Excel or Google Sheets.
The CSV parser handles quoted fields containing commas and escaped double quotes — the parts of the format that break naive implementations. The JSON side accepts any array of objects; missing fields become empty cells in the CSV output.
Nested JSON (objects inside objects) is flattened for CSV export using dot notation, and the JSON output keeps values typed — numbers stay numbers instead of becoming strings.
FAQ
Does it handle Excel exports?
Yes — copy a cell range from Excel or Google Sheets and paste; the tab-separated clipboard content is treated like CSV with the same conversion rules.
What about huge files?
The tool runs in browser memory, so files up to tens of megabytes convert fine. For million-row datasets use a streaming command-line tool instead.
How are nested JSON objects handled in CSV?
They are flattened with dot paths (user.name → a "user.name" column). Importing that CSV back yields the same structure via JSON output.