ConvertFlow Data & Code Suite
Convert Legacy XLS to Modern XLSX Excel Format
Upgrade old binary Excel 97-2003 spreadsheets into modern OpenXML XLSX files.
Convert XLS to XLSX
activeConvert legacy Microsoft Excel 97-2003 binary format (.xls) into modern OpenXML Excel format (.xlsx).
24h Ephemeral Auto-Purge
SuperAdminMax File: 50 MB•Batch: Up to 100 files
Queue:Ultra Dedicated Multi-Region•Unlimited Credits
Choose Files or Drag & Drop here
Accepts formats: XLS (Max 50 MB per file)
How to Convert Convert XLS to XLSX Online
1
Upload .xls file
2
Convert
3
Download .xlsx workbook
Frequently Asked Questions about Convert XLS to XLSX
Are multiple sheets retained?
Yes, all worksheets in the workbook are preserved.
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