A CSV export opens in Excel with everything in one column, dates as text and Arabic names turned into question marks. This page reads the file properly and writes a real .xlsx workbook, on your device.
The separator is detected automatically (comma, semicolon or tab), numbers and dates become real numbers and dates, and text that was mangled by the wrong encoding is repaired. Large exports with hundreds of thousands of rows are fine.
Nothing is uploaded — a customer list or a bank export stays on your computer.
How to use it
Drop the CSV (or TSV) file.
Check the preview: columns, numbers and dates should already look right.
Excel (.xlsx) is selected as the export format.
Press Export and download the workbook.
Supported formats and limits
Input
CSV, TSV, text with any separator
Output
Excel .xlsx (or JSON)
Size
Hundreds of thousands of rows; limited by device memory
Where it runs
In your browser; nothing uploaded
Not for: Formulas — a CSV has none, so the workbook contains values only.
Frequently asked questions
Are my files uploaded to a server?
No. This conversion runs entirely inside your browser using your own device’s processing power. The file never leaves your computer or phone, which is why it also works when your connection drops.
Why did Excel show my CSV in one column?
Because the file used a semicolon or a tab as separator and Excel guessed comma. This tool detects the separator instead of guessing.
Will Arabic and accented characters be fixed?
Yes. Text broken by the wrong encoding is repaired automatically on the way in.
Can I split a huge CSV into several Excel files?
Yes. The split tab divides it by row count or by target file size, keeping the header row in every part.