Excel to CSV Converter

About Excel to CSV Converter

Excel to CSV Converter is a free online tool that converts Excel spreadsheet files (.xlsx and .xls) into CSV (Comma-Separated Values) format. Select an Excel file, choose a sheet and delimiter, then download your CSV file—all processed locally in your browser for complete privacy.

Why convert Excel to CSV?

CSV is a universal format supported by virtually all data processing tools. Converting Excel to CSV is essential for:

- Importing data into databases (MySQL, PostgreSQL, etc.)
- Processing data with programming languages (Python, R, JavaScript)
- Using data with command-line tools and scripts
- Importing into web applications and APIs
- Sharing data across different platforms
- Reducing file size for storage or transfer
- Ensuring compatibility with older systems

CSV files are plain text, making them more portable and easier to version control than binary Excel files.

What Excel formats are supported?

This tool supports both modern and legacy Excel formats:

- .xlsx (Excel 2007 and later) - Modern XML-based format
- .xls (Excel 97-2003) - Legacy binary format

Both formats are fully supported with all features including:
- Multiple sheets
- Various data types (text, numbers, dates, formulas)
- Large spreadsheets (thousands of rows)
- Special characters and Unicode text

How do I choose which sheet to convert?

If your Excel file contains multiple sheets (worksheets), you can select which one to convert:

1. Upload your Excel file
2. The Sheet Select dropdown will populate with all available sheets
3. Choose the sheet you want to convert
4. Click 'Convert to CSV'

The tool shows the sheet name so you can easily identify the correct one. If your file has only one sheet, it will be selected automatically.

What delimiter options are available?

Choose the delimiter that best fits your needs:

- Comma (,) - Standard CSV format, most widely supported
- Semicolon (;) - Common in European locales where comma is decimal separator
- Tab (\t) - TSV format, useful for data with commas
- Pipe (|) - Alternative for data with commas and tabs
- Custom - Specify any character you need

The delimiter determines how values are separated in your CSV file. Choose based on your target application's requirements.

What about formulas in my Excel file?

The converter exports the calculated values of formulas, not the formulas themselves. For example:

- If cell A1 contains =SUM(B1:B10) with result 150
- The CSV will contain 150, not the formula

This is the standard behavior because:
- CSV format doesn't support formulas
- Most applications need the actual values, not formulas
- Values are ready to use immediately in databases or scripts

If you need to preserve formulas, consider exporting as a different format or keeping the original Excel file.

Does my data leave my device?

No. All Excel to CSV conversion happens entirely in your browser using JavaScript. Your file:

- Never uploads to any server
- Never leaves your computer
- Is processed completely client-side
- Remains private and secure

You can verify this by:
- Disconnecting from internet after page loads (tool still works)
- Checking browser network tab (no file uploads)

This makes the tool safe for sensitive data like financial records, customer information, or confidential business data.

What's the difference between UTF-8 and UTF-8 with BOM?

Both are Unicode encodings that support international characters:

UTF-8 (Recommended):
- Standard encoding for most applications
- Compatible with modern tools and programming languages
- Smaller file size
- Best for: APIs, databases, programming

UTF-8 with BOM:
- Includes a Byte Order Mark at the start of file
- Helps Excel and some Windows tools recognize UTF-8 encoding
- Slightly larger file size
- Best for: Opening in Excel, Windows Notepad, legacy applications

If your CSV will be opened in Microsoft Excel, UTF-8 with BOM ensures proper display of special characters (é, ñ, 中, etc.). For most other uses, standard UTF-8 is preferred.

Can I convert large Excel files?

Yes, this tool can handle large Excel files, but performance depends on your device:

Typical performance:
- Small files (< 1 MB, few thousand rows): Instant
- Medium files (1-10 MB, tens of thousands rows): A few seconds
- Large files (10-50 MB, hundreds of thousands rows): 10-30 seconds
- Very large files (> 50 MB): May take longer or require more memory

Tips for large files:
- Close other browser tabs to free memory
- Use a modern browser (Chrome, Firefox, Edge)
- If conversion fails, try splitting the Excel file into smaller sheets
- Consider using desktop tools for files over 100 MB

The tool processes everything in browser memory, so available RAM is the main limitation.