JSON to CSV Converter, Free Online, No Upload

Nested objects are flattened using dot notation for column names. For example, {"address": {"city": "NYC", "zip": "10001"}} becomes two columns: "address.city" with value "NYC" and "address.zip" with value "10001". Nested arrays are joined into a comma-separated string within a single cell by default.

Yes. Select comma as the delimiter for maximum compatibility with Excel. The output is a standard .csv file that Excel, Google Sheets, LibreOffice Calc, and all major spreadsheet applications open natively. For European versions of Excel that use semicolons, select the semicolon delimiter instead.

A JSON array of objects, like [{"name": "Alice", "age": 30}, {"name": "Bob", "age": 25}]. Each object becomes a row, and each unique key becomes a column header. A single JSON object (not in an array) is also supported and converts to a single-row CSV.

Upload the file using the file upload button rather than pasting. The converter processes files locally using your device hardware, so large files (10,000+ records) work fine on modern devices. Processing time depends on file size and your device speed — a 50,000-record file typically converts in a few seconds.

Yes. Copy the JSON response body from your API client (Postman, Insomnia, browser DevTools) and paste it directly into the input field. If the API returns a wrapper object like {"data": [{...}]}, paste only the array portion or the converter will attempt to flatten the wrapper.

CSV (Comma-Separated Values) uses commas as delimiters. TSV (Tab-Separated Values) uses tabs. TSV is useful when your data contains commas (like addresses). Select "tab" as the delimiter in this converter to produce TSV output. Both formats are supported by Excel and Google Sheets.

Paste your JSON array into the input pane (or upload a .json file), choose comma as the delimiter for Excel compatibility, then click Download to save the CSV. There is no upload, no signup, no email gate. Modern V8 parses JSON at roughly 80–100 MB/s, so a typical 10,000-record API response converts in well under 100 ms.

Yes. Nested objects are flattened with dot notation by default — the same convention used by pandas `json_normalize` and Power Query. So `{"address": {"city": "NYC"}}` becomes a column named `address.city`. For nested arrays you can either join values into a single cell or explode them into multiple rows.

Yes. Paste output from `mongoexport`, Firebase BigQuery exports, Postman saved responses, or Airtable exports directly. JSON is defined by RFC 8259 (Tim Bray, Dec 2017) and parallel ECMA-404 — any spec-compliant JSON parses cleanly here.

Excel for Windows requires a UTF-8 byte-order mark (the three bytes `EF BB BF`) at the start of the file or it falls back to Windows-1252 and mojibakes accented characters. This converter writes the BOM by default, so accented text in names, addresses, and product titles renders correctly in Excel for Windows.