SDC to XLSM Converter

SDC is the legacy spreadsheet format used by StarOffice Calc and early OpenOffice.org releases, the predecessor suites to LibreOffice Calc. It stores cell data, formulas, and formatting using StarOffice's original binary document model, which was superseded by the OpenDocument Spreadsheet (ODS) standard. SDC files typically surface today only when working with archived StarOffice-era spreadsheets.

LibreOffice Calc opens SDC files natively through its built-in legacy StarOffice format support, converting the spreadsheet into its modern editing environment automatically. Apache OpenOffice Calc also supports this older format.

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.