XLS → XLSX

Convert legacy XLS files into modern XLSX format. Fast, secure, and easy-to-use XLS → XLSX tool.

Batch Processing: Convert multiple XLS files at once.

About this tool

The XLS → XLSX converter upgrades Microsoft Excel 97-2003 spreadsheets (.xls) to modern Excel Open XML format (.xlsx). XLSX provides better performance, compatibility, and advanced features not available in legacy XLS files.

How to use:

Upload your .xls file using the upload area above.
Click Convert to begin the process.
Wait while the file is converted to .xlsx.
Download and open the new Excel file in any modern spreadsheet software.

Features:

Converts legacy XLS files to modern XLSX format
Preserves formulas, tables, and formatting
Improves compatibility with current Excel and other spreadsheet tools
Fast and secure online conversion
No installation required

Notes:

Input format: .xls
Output format: .xlsx
Extremely old XLS files may have limited formatting compatibility
Converted XLSX files are fully editable

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Frequently Asked Questions

Can I convert multiple XLS files at once?

Yes, batch processing is supported.

Will formulas be preserved?

Yes, most formulas are retained in the XLSX file.

Do I need to install software?

No, conversion happens entirely online in your browser.

Are my files secure?

Yes, uploaded files are deleted after processing.

Is this tool free?

Completely free to use.