Xls is the file extension for Microsoft Excel files. It is a spreadsheet format and supports a series of cells that contain data. Rtf files are rich text format documents that contain simple text data. Rtf is compatible with a wide variety of software platforms (word processing and other). You might need to convert your spreadsheet file to this simple text format so that it is compatible with another program. Keep in mind that you need access to Microsoft Office programs (Excel and Word) in order to perform this conversion.
Open the .xls file in Microsoft Excel. Click "File" then "Save As" on the main menu.
Select "Text (Tab Delimited)" from the "Save as type" dialog box. Save the file to your computer and then close the Excel program. If prompted, select the option to save the active worksheet only (you will have to save each worksheet of your .xls file individually).
Open Microsoft Word. Click "File" then "Open" and find the text file that you just saved. If you don't see it in the file list, choose "All Files" from the "Files types" drop down list in the dialog box to display all file extensions. Open the file.
Click "File" then "Save As" on the Word main menu. Choose "Rich Text Format" from the "Save as type" drop down list and then hit "Save." You now have a .rtf (rich text format) version of your original Excel file.