Convert a CSV file to an Excel workbook (.xlsx). The separator and character set are detected; numbers and dates become real numbers and dates, and a code like 0012 stays 0012.
Good to know
The character set (UTF-8, or Windows-1252 from an older Excel), the separator (comma, semicolon, tab or vertical bar) and whether numbers are written the Dutch way (1.234,50) or the English way (1,234.50). If the detection is wrong, choose yourself; the preview immediately shows how the cells will turn out.
Numbers become real numbers you can calculate with, also with a euro or percent sign; dates such as 01-02-2026 or 2026-02-01 become real dates, day first. A postcode, product code or phone number with a leading zero (0012, 0612345678) and long digit strings such as an EAN or account number stay text, so no digits are lost. Everything happens in your browser; the file is not uploaded.