Convert an uploaded XLSX workbook sheet to CSV or JSON locally in the browser.
This converter reads an XLSX workbook in the browser and exports the selected sheet as CSV, JSON or a compact sheet summary. It is useful when you need a quick copyable extract without uploading a spreadsheet to a server.
How it works
Choose an Excel workbook, enter the sheet name or leave the sheet field blank for the first sheet, then convert. A demo workbook preset is included for testing the output without selecting a file.
Privacy note
The workbook is parsed locally with a bundled library from /libs/. Large files can still be slow in the browser.