XLSM to OTS Converter

The XLSM format is a macro-enabled spreadsheet file created by Microsoft Excel 2007 and later versions, utilizing the Office Open XML (OOXML) standard (ISO/IEC 29500). Unlike the standard XLSX format, XLSM files store embedded macros written in Visual Basic for Applications (VBA), allowing for automation and complex scripting within the workbook. The file structure relies on ZIP compression to contain XML documents for data, styles, and macro binary parts (vbaProject.bin), presenting a security risk that often requires user authorization to execute active content.

XLSM files open natively in Microsoft Excel (2007+) on Windows and macOS, which provides full VBA execution support. For non-Microsoft environments, LibreOffice Calc, OpenOffice Calc, and WPS Office can open these files and view data, though VBA macro execution compatibility varies significantly. Google Sheets can import XLSM data but strips the VBA macros, converting the file to its native format without automation features.

The OpenDocument Spreadsheet Template (OTS) is a file format defined by the OASIS OpenDocument standard (ISO/IEC 26300) specifically for creating reusable spreadsheet blueprints. Structurally identical to the ODS format, it uses ZIP compression to package XML content and styles. The primary technical distinction lies in the file header flags, which instruct the software to open a new, untitled instance of the spreadsheet rather than modifying the original template file, preserving the source data structure and formulas.

OTS files function seamlessly with ODF-compliant software including LibreOffice Calc and Apache OpenOffice across all major operating systems. While Microsoft Excel can open these files, users may need to manually select the file type in the open dialog. Double-clicking an OTS file typically launches a new workbook based on the template rather than opening the template file itself for editing.