Convert XLS (Excel) to XLSX (Excel)

The XLS file extension, short for "Excel Spreadsheet", is a legacy format used by Microsoft Excel for storing spreadsheet data. Introduced with Excel 2.0 in 1987, it was the primary format until the introduction of XLSX in 2007. XLS files contain data organized in rows and columns, supporting formulas, macros, and various formatting options, making them essential for data analysis and financial reporting. Despite being replaced by the more robust and secure XLSX format, XLS files remain widely used in many legacy systems and applications.

The XLSX file extension, standing for "Excel Spreadsheet", represents a widely used format for Microsoft Excel spreadsheets. Introduced in Excel 2007, XLSX replaced the older XLS format, utilizing the Office Open XML (OOXML) standard to store data more efficiently and reduce file size. It supports advanced features such as pivot tables, charts, formulas, and macros, essential for data analysis and reporting in various professional settings. The transition to XLSX provided enhanced security, improved data recovery, and greater compatibility with other software applications, solidifying its status as a pivotal tool in data management and business intelligence.