| File extension | Developer/Producer | File description |
|---|---|---|
| $$S file extension | IBM | OS/2 Spreadsheet Format |
| 123 file extension | IBM | Lotus 1-2-3 Spreadsheet Format |
| AWSS file extension | N/A | Microsoft Works For Mac Spreadsheet |
| BKS file extension | Microsoft | Microsoft Works Spreadsheet Document Backup Format |
| CSVX file extension | N/A | XML CSV |
| CWSS file extension | Apple, Inc. | ClarisWorks Spreadsheet |
| DEF file extension | SmartWare | SmartWare II Data Format |
| DEX file extension | Microsoft | Microsoft Excel Spreadsheet Format |
| DFG file extension | Interscape | Data Flask Grid Format |
| DIS file extension | Oracle | Oracle Discoverer Workbook Format |
| DWK file extension | DSP Development Corporation | DADiSP Worksheet |
| ECSV file extension | N/A | Encapsulated Comma Separated Value |
| EDX file extension | EdrawSoft | EDraw Max Drawing Format |
| EDXZ file extension | EdrawSoft | Edraw Compressed XML FIle |
| ESS file extension | N/A | EasySpreadsheet Spreadsheet Format |
| FCS file extension | N/A | First Choice Spreadsheet |
| FM file extension | FileMaker | FileMaker Pro Database Format |
| FM1 file extension | IBM | Lotus 1-2-3 Release 2.x Spreadsheet |
| FODS file extension | Oracle | OpenDocument Flat XML Spreadsheet Format |
| FP file extension | N/A | FileMaker Pro Database Format |
| GSHEET file extension | Link To Google Sheets Web Application Spreadsheet Document | |
| JNB file extension | Systat Software Inc. | SigmaPlot Workbook |
| KSP file extension | KDE e.V | Calligra Sheets Spreadsheet |
| LSS file extension | N/A | Legato Spreadsheet |
| MAR file extension | Mariner Software | Mariner Calc Spreadsheet Format |
| NB file extension | Wolfram Research | Mathematica Notebook Format |
| NMBTEMPLATE file extension | Apple | Apple Numbers Spreadsheet Template Format |
| NUMBERS file extension | Apple | Apple Numbers Spreadsheet Format |
| NUMBERS-TEF file extension | Apple | Apple Numbers ICloud Spreadsheet Format |
| ODS file extension | Sun Microsystems | OpenDocument Spreadsheet Format |
| OGW file extension | OriginLab Corporation | OriginLab Worksheet |
| OTS file extension | N/A | OpenOffice.org OpenDocument Spreadsheet Template Format |
| PMV file extension | SoftMaker Software | PlanMaker Spreadsheet Template Format |
| QPW file extension | Corel | Corel Quattro Pro Spreadsheet Format |
| QVO file extension | QlikTech International AB | QlikView Table |
| RDF file extension | N/A | Report Definition Format |
| RS1 file extension | Natural Resources Canada | RETScreen Spreadsheet |
| SDC file extension | Oracle | OpenOffice.org Spreadsheet Format |
| SILK file extension | Microsoft Corporation | Microsoft Excel Symbolic Link Format |
| SKY file extension | Microsoft Corporation | Microsoft Multiplan SYLK Spreadsheet |
| SLS3 file extension | Microsoft Corporation | Microsoft Excel 3 For Mac Template |
| SLS4 file extension | Microsoft Corporation | Microsoft Excel 4 For Mac Template |
| SLS5 file extension | Microsoft Corporation | Microsoft Excel 5 For Mac Template |
| SLS8 file extension | Microsoft Corporation | Microsoft Excel 98 For Mac Template |
| SMX file extension | StatSoft, Inc. | Statistica Matrix Spreadsheet |
| SPW file extension | Quantitative Software Management. Inc. | SLIM-Master Plan Workbook |
| STC file extension | Sun Microsystems | OpenOffice.org Calc Spreadsheet Template Format |
| SWSS file extension | Apple, Inc. | ClarisWork Spreadsheet |
| SXC file extension | Sun Microsystems | OpenOffice.org 1.0 Spreadsheet Format |
| SXLS file extension | N/A | Sealed Excel Spreadsheet |
| SXLSX file extension | N/A | Sealed Microsoft Excel 2007 Worksheet |
| SYK file extension | Microsoft Corporation | Microsoft Excel Symbolic Link Format |
| TII file extension | Texas Instruments Inc. | Texas Instruments TI InterActive! Workbook |
| UOS file extension | N/A | Unified Office Format Spreadsheet Format |
| WB0 file extension | Corel Corporation | Corel Quattro Pro Spreadsheet |
| WB? file extension | Corel Corporation | Corel Quattro Pro Spreadsheet |
| WG1 file extension | IBM | Lotus 1-2-3 Worksheet |
| WG2 file extension | IBM | Lotus 1-2-3 For OS/2 Worksheet |
| WK! file extension | IBM | Lotus 1-2-3 Spreadsheet |
| WKQ file extension | Corel Corporation | Corel Quattro Pro For MS-DOS Spreadsheet |
| WKS file extension | Microsoft | Microsoft Works Spreadsheet Document Format |
| WKU file extension | N/A | Lotus 1-2-3 Spreadsheet Format |
| WKZ file extension | Informix | Wingz Spreadsheet |
| WQ! file extension | Corel Corporation | Corel Quattro Pro Compressed Spreadsheet |
| WQ0 file extension | Corel Corporation | Corel Quattro Pro For MS-DOS Spreadsheet |
| WQ1 file extension | Corel | Corel Quattro Pro For MS-DOS Spreadsheet Format |
| WQ2 file extension | Corel | Corel Quattro Pro For MS-DOS Spreadsheet Format |
| WQ? file extension | Corel Corporation | Corel Quattro Pro For MS-DOS Spreadsheet |
| WR! file extension | IBM | Compressed Lotus Spreadsheet |
| WR1 file extension | IBM | Lotus Symphony Spreadsheet |
| WSS file extension | N/A | Microsoft Works For Mac Spreadsheet |
| XCEL file extension | Microsoft Corporation | Microsoft Excel For Mac Spreadsheet |
| XL file extension | Microsoft | Microsoft Excel Spreadsheet Format |
| XLMX file extension | Microsoft Corporation | Microsoft Excel Macro-enabled Spreadsheet |
| XLR file extension | Microsoft | Microsoft Works Spreadsheet Or Chart Format |
| XLS file extension | Microsoft | Microsoft Excel 97 To 2003 Workbook Format |
| XLS3 file extension | Microsoft Corporation | Microsoft Excel 3 For Mac Spreadsheet |
| XLS4 file extension | Microsoft Corporation | Microsoft Excel 4 For Mac Spreadsheet |
| XLS5 file extension | Microsoft Corporation | Microsoft Excel 5 For Mac Spreadsheet |
| XLS8 file extension | Microsoft Corporation | Microsoft Excel 98 For Mac Spreadsheet |
| XLSB file extension | Microsoft | Microsoft Excel 2007/2010 Binary Workbook Format |
| XLSHTML file extension | Microsoft | Microsoft Office Excel HTML Document Format |
| XLSM file extension | Microsoft | Microsoft Excel 2007/2010 Open XML Macro-enabled Workbook Format |
| XLSMHTML file extension | Microsoft | Microsoft Excel MIME HTML Spreadsheet Format |
| XLSX file extension | Microsoft | Microsoft Excel 2007, Excel 2010 And Excel 2013 Open XML Workbook Format |
| XLS_ file extension | Microsoft Corporation | Microsoft Excel For Mac Spreadsheet |
| XLTHTML file extension | Microsoft | Microsoft Office Excel HTML Template Format |
| XLTM file extension | Microsoft | Microsoft Excel 2007/2010 Open XML Macro-enabled Workbook Template Format |
| XLTX file extension | Microsoft | Microsoft Excel 2007/2010 Open XML Workbook Template Format |
| XLW3 file extension | Microsoft Corporation | Microsoft Excel 3 For Mac Workbook |
| XLW4 file extension | Microsoft Corporation | Microsoft Excel 4 For Mac Workbook |
| XLW5 file extension | Microsoft Corporation | Microsoft Excel 5 For Mac Workbook |
| XLW_ file extension | Microsoft Corporation | Microsoft Excel 2 For Mac Workbook |
| XLXML file extension | Microsoft Corporation | Microsoft Excel XML Worksheet |
| XMLX file extension | Microsoft Corporation | Excel Spreadsheet |
| XS4 file extension | AIS | XESS Worksheet |
| XS5 file extension | AIS | XESS Worksheet |
| _XLS file extension | Microsoft Corporation | Microsoft Excel Workbook |
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