Question 1

What happens with multi-sheet Excel workbooks?

Accepted Answer

You can pick which sheet to convert from a dropdown listing every sheet in the workbook. Each conversion produces one CSV file for one sheet — convert again to export a different sheet.

Question 2

Will number and date formatting be preserved?

Accepted Answer

Numbers convert as their raw values. Dates are converted based on how Excel stored them, which usually matches what you see in the spreadsheet, but heavily custom date formats may not carry over exactly since CSV has no concept of cell formatting.

Question 3

What happens to formulas in my spreadsheet?

Accepted Answer

CSV only stores values, not formulas — cells with formulas export as their last calculated value.

Question 4

Can I convert a CSV file with a single sheet back to XLSX?

Accepted Answer

Yes — the CSV → XLSX direction creates a new workbook with one sheet named "Sheet1" containing your data.

Question 5

Is my spreadsheet uploaded to a server?

Accepted Answer

No. Conversion happens entirely in your browser using the SheetJS library — your file never leaves your device.

XLSX to CSV Converter

Result

Frequently Asked Questions

What happens with multi-sheet Excel workbooks?

Will number and date formatting be preserved?

What happens to formulas in my spreadsheet?

Can I convert a CSV file with a single sheet back to XLSX?

Is my spreadsheet uploaded to a server?

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