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Welcome to the File Converter

Upload your file to start converting. Choose a file from your device or use a remote file link.

${shortenFileName(item.file_name)} ${formatBytes(item.file_size)}
Output:
Add ${items.length} files

How to Convert Xls to XLSX?

  1. Click the “Choose XLS Files” button and select your XLS file
  2. Click on the “Convert” button to start the conversion
  3. When the status changes to “Done”, click the "Download XLSX" button

Convert Any XLS to XLSX

This tool supports converting many types of Xls to XLSX. Convert XLSX, PDF, CSV, ODS, TXT, HTML, XML, DOCX AND RTF to XLSX.

Best Xls Converter

Convert your Xls with perfect quality, size, and compression. Plus, you can also batch convert Xls using this tool.

Free & Secure

Our Xls Converter is free and works on any web browser. We guarantee file security and privacy. Files are protected with 256-bit SSL encryption and automatically delete after a few hours.

XLS is the early binary file format used by Microsoft Excel for storing spreadsheet data. It is widely used in data analysis, financial management, and business reporting. Unlike the modern XLSX format, XLS uses binary encoding and supports basic formula calculations and charts. Although XLS has been replaced by XLSX as the default format, many legacy systems and applications still rely on XLS for data exchange.

XLSX is the modern file format used by Microsoft Excel, based on the Office Open XML standard, for storing spreadsheet data. It supports larger datasets, more complex formulas, charts, and styles, widely used in data analysis, financial reports, and business presentations. Compared to the older XLS format, XLSX offers better compatibility and enhanced security, making it suitable for various applications.

Your Data, Our Priority

At AllConverter, we go beyond just converting files—we protect them. Our robust security framework ensures that your data is always safe, whether you're converting an image, video, or document. With advanced encryption, secure data centers, and vigilant monitoring, we've covered every aspect of your data's safety.

Learn more about our commitment to security

SSL/TLS Encryption
Secured Data Centers
Access Control and Authentication
Firewall & IDS/IPS