Convert XLS to XLSX Online
XLS is the spreadsheet format of Microsoft Excel 97–2003, still common in old reports and exports. Upload your XLS files, click "Convert" and download the result as XLSX. XLSX opens in Excel, Google Sheets, LibreOffice Calc and Numbers, with sheets and formatting kept.
The conversion runs on our server and takes a few seconds. Files are sent over an encrypted connection and deleted automatically after 48 hours.
Why Use This XLS to XLSX Converter?
- An XLSX that opens in Excel and Google Sheets
- Several files at once, up to 1 GB each
- Encrypted connection, files deleted after 48 hours
- Free, no registration, no watermark
How to Convert XLS to XLSX
- Select or drag your XLS files into the upload area
- Click "Convert" and wait a few seconds
- Download the XLSX files
Frequently Asked Questions
Is this XLS to XLSX converter free?
Yes, it is completely free, with no registration and no watermark.
What is a XLS file?
XLS is the spreadsheet format of Microsoft Excel 97–2003, still common in old reports and exports.
Why convert XLS to XLSX?
XLSX opens in Excel, Google Sheets, LibreOffice Calc and Numbers, with sheets and formatting kept.
Are my files safe?
Files are sent over an encrypted connection and deleted from our server automatically after 48 hours; you can delete them earlier in "Your files".