How to use the CSV to Excel Converter
- Paste CSV, or click Open file and choose one or more .csv files.
- Check the preview. The delimiter (comma, semicolon or tab) is detected for you.
- Keep Keep leading zeros & long numbers on for IDs, phone numbers and ZIP codes.
- Click Download .xlsx.
Problems this fixes
| In the CSV | Double-click in Excel | This converter |
|---|---|---|
00501 (ZIP code) | 501 | 00501 |
0812345678 (phone) | 812345678 | 0812345678 |
4012888888881881 (16-digit ID) | 4.01289E+15, last digit lost | 4012888888881881 |
กรุงเทพ, café | Garbled characters | กรุงเทพ, café |
2026-10-24 | Sometimes a date, sometimes text | A real date |
| Semicolon-separated file | Everything in column A | Split into columns |
Combine CSV files
Choose several files at once and each becomes its own sheet in one workbook, named after the file. Handy for monthly exports or reports from different systems.
Private and offline
The workbook is built in your browser. Nothing is uploaded, so customer lists and financial exports stay on your device. Need the opposite? Use Excel to CSV.
Frequently asked questions
Will Excel open the file?
Yes. It's a standard .xlsx file, which Excel 2007 and later, Google Sheets, Numbers and LibreOffice all open.
Why are some numbers left-aligned as text?
Values with leading zeros or more than 15 digits are kept as text on purpose, because Excel can't store them as numbers without changing them. Untick Keep leading zeros & long numbers to convert them anyway.
How big can the CSV be?
Large files with hundreds of thousands of rows work on most computers. Excel allows up to 1,048,576 rows per sheet.
Is my file uploaded?
No. Everything happens in your browser.
Updated