Convert CSV data into a downloadable .xlsx spreadsheet | 100% Private
Paste CSV text directly, or upload a .csv file from your device — whichever is easier.
Comma, semicolon, or tab — pick the delimiter that matches your data.
See exactly how your data will look before downloading the spreadsheet.
Generates a genuine Excel file, not a renamed CSV — opens perfectly in Excel and Sheets.
Conversion happens entirely in your browser. Your data is never uploaded anywhere.
Empty input or malformed rows show a clear message instead of crashing the page.
CSV (Comma-Separated Values) is a simple, universal text format for tabular data, but it lacks formatting, multiple sheets, and the rich features of a real spreadsheet. Converting CSV to a genuine .xlsx file makes your data instantly compatible with Excel, Google Sheets, and other spreadsheet applications.
Not all CSV files use a comma. European locales often export CSV with semicolons because the comma is used as a decimal separator, while tab-separated files (TSV) are common for copy-pasted spreadsheet data. Choosing the correct delimiter here ensures your columns are split correctly rather than merged into one.
Your CSV text is parsed into rows and columns based on the selected delimiter, then handed to the SheetJS library's aoa_to_sheet() function to build an in-memory worksheet, which is then written out as a downloadable .xlsx file using XLSX.writeFile() — all directly in your browser, with no server involved.
Yes. The tool generates a genuine .xlsx spreadsheet file (Office Open XML format) that opens directly in Microsoft Excel, Google Sheets, LibreOffice Calc, and Apple Numbers.
Yes. You can either paste CSV text directly into the textarea or upload a .csv file from your device — both are parsed the same way.
You can choose comma, semicolon, or tab as the field delimiter, which covers the most common CSV export formats used by different regions and applications.
No. The entire conversion — parsing the CSV and building the .xlsx file — happens locally in your browser using the SheetJS library. Your data is never transmitted anywhere.
Yes. The parsed data is shown as a table preview so you can confirm the delimiter and structure are correct before downloading the .xlsx file.