XLS
Excel 97–2003 workbook
XLS is the binary workbook format of Excel 97–2003. Many older systems and bank or accounting exports still produce it.
Extensions: .xls .xlt
XLS to XLSX converter
Convert XLS files to XLSX on Windows 10 and 11: free, offline and in batches. Drag the files onto XLSX in Filee's format donut and the XLSX files appear next to the originals.
How to convert XLS to XLSX on Windows
- 1
Select your XLS files
In File Explorer or on the desktop, select one XLS file or as many as you like.
- 2
Hold Ctrl and drag
Hold Ctrl (or the key you set in Filee) and drag the files. A donut of formats opens at the cursor. Prefer menus? Right-click and choose Convert with Filee.
- 3
Drop on XLSX
Release the files over XLSX. A progress ring counts up, and each XLSX file is saved next to its original.
What Filee does for XLS → XLSX
Upgrade old Excel 97–2003 workbooks without Excel or LibreOffice: the conversion is built in. XLSX files are usually smaller, can't carry macros and open in every current spreadsheet app.
- Built in: works right after installing Filee, with nothing else to download.
- Batch: one file or hundreds, converted in parallel; a failure never stops the rest.
- Private: files are converted on your PC and never uploaded, even without internet.
- Saved next to the original, or in a folder and with a file name pattern you choose.
XLS can also become
- CSV
- ODS
- HWPX
- HTML
About XLS and XLSX
XLSX
Excel workbook
XLSX is the Microsoft Excel workbook format since Excel 2007. One workbook can hold several sheets with formulas, formatting, charts and pictures.
Extensions: .xlsx
Convert XLS to XLSX for free
Filee is a free, open-source file converter for Windows 10 and 11. It works offline and converts 180+ formats with one drag and drop.
Download for Windows