Short answer: Both XLS and XLSX formats are fully supported.
Whether you're using the latest version of Microsoft Excel or working with older spreadsheet files, CSV2Invoice handles both major Excel formats seamlessly.
Supported Excel Formats
XLSX (Modern Excel)
The XLSX format is the default format for:
- Microsoft Excel 2007 and later
- Google Sheets (when exported as Excel)
- LibreOffice Calc
- Apple Numbers (when exported as Excel)
XLSX files use XML-based structure and support larger spreadsheets, more formatting options, and modern Excel features.
XLS (Legacy Excel)
The XLS format was used by:
- Microsoft Excel 97-2003
- Older spreadsheet applications
- Legacy business systems
Even though XLS is an older format, we fully support it for businesses working with legacy data or older Excel versions.
No Conversion Required
You don't need to worry about which format your file is in. Simply upload your Excel file, and our system automatically detects and processes either format.
Format Compatibility
- XLSX: Excel 2007+, Google Sheets, modern spreadsheets
- XLS: Excel 97-2003, legacy systems
- Both formats: Work identically in CSV2Invoice
- No preparation: Upload directly without conversion
Which Format Should I Use?
It doesn't matter! Both formats work equally well for invoice generation. Use whichever format your system exports:
- Modern Excel users: XLSX is your default format
- Legacy systems: XLS works perfectly fine
- Google Sheets: Export as Excel (XLSX)
- Mixed sources: Upload whichever format you have
Our Excel to invoice generator treats both formats identically, so you can focus on your data rather than file format compatibility.
What About Other Spreadsheet Formats?
While we specialize in Excel formats (XLS and XLSX), you can use other spreadsheet applications by exporting to Excel format:
- Google Sheets: File → Download → Microsoft Excel (.xlsx)
- LibreOffice: Save as .xlsx or .xls
- Apple Numbers: Export as Excel
- OpenOffice: Save as Microsoft Excel format
Technical Details
For those interested in the technical differences:
- XLSX: XML-based, better compression, supports more rows/columns
- XLS: Binary format, widely compatible, proven reliability
- Data extraction: Identical for both formats in CSV2Invoice