CSV / Excel変換

This is a two-way CSV and Excel converter: turn CSV text into a downloadable .xlsx workbook, or read an Excel file and export any sheet as CSV. Pick the direction, paste or upload, and get the converted file.

It is the bridge between the plain-text world of CSV, which APIs, databases and scripts love, and the spreadsheet world of Excel, which is where most people actually view and edit tabular data.

It uses SheetJS and runs locally in your browser, so your spreadsheet never leaves your device, which matters for the financial and personal data spreadsheets often hold.

When converting Excel to CSV, you can choose which sheet to export, since a CSV file holds a single table. Converting CSV to Excel produces a workbook with one sheet containing your data.

It reads modern .xlsx files and older .xls files, and always outputs the modern .xlsx format, so the result opens cleanly in current versions of Excel, Google Sheets, LibreOffice and similar tools.

Because CSV is just values, the conversion focuses on the data itself. Cell values, rows and columns transfer faithfully, while complex spreadsheet features like formulas, charts and styling are outside what a CSV can carry.