CSV to Excel

CSV is plain text, so it has no types, no formatting and no sheets. Opening one straight in Excel makes Excel guess: leading zeros vanish, part numbers turn into dates and accented letters can come out garbled. This converter builds a real Excel workbook (.xlsx) from your CSV instead, so you decide what each value becomes.

The CSV is read with full support for quoted fields, embedded commas and line breaks, and comma, semicolon, tab or pipe delimiters. Values that round-trip as numbers, such as 42 or -3.5, are stored as Excel numbers you can sum and chart. Anything else, including 007, 1.50, long IDs and dates, is stored as text exactly as written, so nothing is changed behind your back. Turn off typed values to store every cell as text.

The workbook has one sheet named Sheet1. The header row is bold and frozen at the top, and each column is sized to its longest value, up to a maximum width. All text is stored as Unicode, so emoji, accents and Chinese or Japanese characters stay intact. Cells longer than Excel's limit of 32,767 characters are cut short, with a note.