This article explains what XLSM files are, how to open them on all your devices, and how to convert them to another file format.

A file with the XLSM file extension is a workbook file that contains Excel macros created in Excel 2007 or later.

These files are identical to Microsoft Excel Open XML Format Spreadsheet (XLSX) files, except that XLSM files execute embedded macros programmed in the Visual Basic for Applications (VBA) programming language.

Similar to XLSX files, this format uses XML and ZIP to store things like text and formulas in cells organized into rows and columns. The data can be cataloged in separate sheets, all stored in a single workbook file.