.xl is the file extension for Excel documents.
Normally xls is the extension for an Excel spreadsheet document.
* The file extension of a Word document is .doc * The file extension of an Excel speadsheet is .xls
An Excel Book or Excel Workbook with the files extension of .xlsx
For most typical Word documents the extension is .docFor Excel workbooks (spreadsheets) the extension is .xlsIn general the file extension is the 3 letter/number "code" after the period in the complete file name that gives a hint as to what type of file it is. For example, in the file name resume.docthe word resume is the file's actual name and the .doc tells you that it is a document file.
The file extension of MS Excel is .xmls
For workbooks in Excel 2003, the extension .xls is used.
XLS is the main extension name used in Excel.
Book1.xls is the default name for a new document in Excel.
The standard extension for Excel workbooks is xls for versions up to 2003. Excel 2007 uses xlsx as its extension for workbooks.
xls, xlsx (2007)
.xls for versions up to Excel 2003 and .xlsx from Excel 2007 onwards.