Convert CSV to XLSX

CSV to XLSX converterFREE

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How to convert CSV to XLSX

Wrong delimiter or encoding at import puts all data in one column or shows garbled text - always verify the import dialog settings before saving.
In many European locales the default CSV separator is a semicolon, not a comma; pick the correct separator in the import wizard.
Excel silently truncates CSV files with more than 1,048,576 rows; split very large files before converting.

Why does my CSV open with all data in one column?

The delimiter in the file does not match what your app expects for your locale. Use the import wizard and manually select comma or semicolon.

Why does the XLSX show garbled characters instead of accented letters?

The CSV is UTF-8 but was opened as the wrong encoding. Re-import using the wizard and select UTF-8 explicitly.

Does converting CSV to XLSX lose any data?

No values are lost if the import settings are correct - you gain Excel structure on top of the original values.

Can I batch-convert many CSV files to XLSX at once?

Yes - use LibreOffice's command-line mode: libreoffice --headless --convert-to xlsx *.csv processes all files in a folder at once.

Learn about the formats: .CSV · .XLSX