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Convert Excel to CSV

Every sheet of a workbook, out as clean UTF-8 CSV.

  • Any sheet, or all of them
  • Dates as YYYY-MM-DD
  • Always UTF-8
  • Nothing uploaded

1.Open the workbook

.xlsx from Excel, Numbers or Google Sheets. Drag it here, or choose a file.

Why it exists

Excel's own "Save as CSV" saves only the sheet you happen to be looking at, writes dates in whatever format the cell displays, and on many systems still defaults to a legacy encoding that turns accented names into question marks. This reads the .xlsx directly, converts any or every sheet, writes dates in one unambiguous format and always writes UTF-8.

What it does

  • Reads .xlsx and .xlsm workbooks from Excel, Numbers, LibreOffice and Google Sheets.
  • Lists every sheet, previews the one you pick, and converts it, or all of them at once into a .zip.
  • Writes date cells as YYYY-MM-DD and date-times as YYYY-MM-DD HH:MM:SS, whatever their display format.
  • Writes each formula's last calculated value, which is what the cell showed.
  • Can add a byte-order mark, so a CSV going back into Excel keeps its accents.

What it leaves out

A CSV holds values and nothing else, so formatting, colours, formulas, comments, charts and merged cells do not survive the trip. That is the nature of the format rather than of the tool. Old binary .xls files are not read; save them as .xlsx first.

Questions

Can I convert every sheet at once?
Yes. The tool reads all of them, and one button writes a CSV per sheet into a single .zip, each named after its sheet.
Why do my dates look different?
Because a CSV cannot carry a display format, only text. Writing every date as YYYY-MM-DD means it reads the same in every country and sorts correctly as text, which is not true of 03/04/2025.
Does it work with .xls files?
No. .xls is the binary format Excel used before 2007, and it is a different file format altogether. Open it in Excel, Numbers or Google Sheets, save it as .xlsx, and convert that.

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