XLS to XLSX

Upgrade legacy Excel 97-2003 files to the modern XLSX format, lifting the old 65,536-row limit and making the file usable in current spreadsheet software.

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Supports .xls; encrypted throughout processing

About XLS to XLSX

Upgrade legacy Excel 97-2003 files to the modern XLSX format, lifting the old 65,536-row limit and making the file usable in current spreadsheet software.

Best for

Modernise archived spreadsheets

Fix compatibility warnings in Excel

Prepare old files for a data import

Frequently asked questions

Is data lost in conversion?

Cell values and formulas carry over. Very old macros are not preserved.

Does the file get bigger?

Usually smaller — XLSX is a compressed format.

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