XLS vs XLSX vs XLSM vs XLSB - Choosing the Right Spreadsheet Format

Last Updated: 10 July, 2026 Compare XLS vs XLSX vs XLSM vs XLSB: Which Excel File Format Should You Use? Microsoft Excel has been the industry standard for spreadsheets for decades, powering everything from personal budgeting to enterprise-level financial analysis. As Excel evolved, several spreadsheet formats emerged to address different needs, including compatibility, storage efficiency, performance, and automation. Today, users often encounter four major Excel file formats: XLS, XLSX, XLSM, and XLSB.
July 10, 2026 · 7 min · Sher Azam Khan