XLS to XLSX Converter
No limits. No uploads. Free.
or drop it here, or press Ctrl+V to paste. Up to 1 GB.
About XLS to XLSX
XLS is the older Excel workbook format with different limits from XLSX. With XLS to XLSX, xLSX is a workbook format, but conversion does not automatically reconstruct formulas from displayed values.
XLS to XLSX starts with browser processing for supported input. A XLS file over 50 MB, or a failed device attempt, can use compatible server processing when capacity is available. That fallback uploads the file and deletes its job after download. The 1 GB selection limit does not guarantee completion.
How to convert XLS to XLSX
- 1
Select the original XLS for your XLSX export. XLS is the older Excel workbook format with different limits from XLSX.
- 2
Start XLS to XLSX with the selected file.
- 3
Save the XLSX result. Review sheet names, column values and cells that should remain text.
Common questions
When is XLS to XLSX useful?
XLS is the older Excel workbook format with different limits from XLSX. XLSX is a workbook format, but conversion does not automatically reconstruct formulas from displayed values.
What should I inspect in the XLSX exported from XLS?
Review sheet names, column values and cells that should remain text. Keep the XLS source until you have confirmed the XLSX is suitable.
What can I use XLS to XLSX for?
XLS is the older Excel workbook format with different limits from XLSX. With XLS to XLSX, xLSX is a workbook format, but conversion does not automatically reconstruct formulas from displayed values.
Will XLS to XLSX preserve nested data and spreadsheet formulas?
Not all formats support nesting, formulas or multiple sheets. Inspect values, columns and the output structure before importing it elsewhere. For XLS to XLSX, Review sheet names, column values and cells that should remain text.
What should I do if XLS to XLSX reports invalid data?
Check that the source is complete and uses the syntax or file format its extension describes. Renaming a file is not conversion. For XLS to XLSX, Review sheet names, column values and cells that should remain text.
Does XLS to XLSX upload my file for processing?
The first XLS to XLSX attempt uses your browser for supported input. A compatible XLS file over 50 MB, or an attempt your device cannot finish, may be sent for server processing if capacity exists. In that case the file is uploaded and the conversion job is deleted after download.