Excel to CSV Converter (XLSX)
Turn any sheet of an Excel .xlsx workbook into a CSV file, with dates written as dates and the separator you choose, in your browser.
Results
What this tool does
Saving as CSV from Excel uses the regional settings of that computer, so the same workbook comes out with commas in one country and semicolons in another, and accented letters often break. Here the workbook is opened by your browser itself, and you choose the separator and whether to add the UTF-8 marker that tells Excel how to read accents when the CSV is opened again. Cells keep the value Excel last calculated, not the formula; dates are written as YYYY-MM-DD, and numbers are rounded to the 15 significant digits Excel works with. Pick the sheet by its number; the list of sheets appears after the file is opened. Older .xls files are a different format and must first be saved as .xlsx.
Formula
each sheet row → one line of text ; fields with the separator, quotes or line breaks go in quotes (RFC 4180)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
rows | Rows read from the workbook | — |
sheet | Sheet number | — |
delimiter | Separator | — |
bom | Start the file with a UTF-8 marker (BOM) | — |
OUT | CSV | — |
RW | Rows | — |
CL | Columns | — |
Worked example
- Rows read from the workbook[["product","price","sold on"],["Pen","1.2","2026-10-17"],["Notebook","3.5","2026-10-18"]]
- Sheet number1
- Separator,
- Start the file with a UTF-8 marker (BOM)1
- CSVproduct,price,sold on Pen,1.2,2026-10-17 Notebook,3.5,2026-10-18
- Rows3
- Columns3
Limitations
- The calculation runs entirely in your browser. The values you type are never sent to a server.