The following tables list all the default file name extensions in Word, Excel, and PowerPoint.

Word

Office Open Xml Zu Pdf

XML file type
Extension
Document
.docx
Macro-enabled document
.docm
Template
.dotx
Macro-enabled template
.dotm

Excel

Office Open Xml Save As Pdf

XML file type
Extension
Workbook
.xlsx
Macro-enabled workbook
.xlsm
Template
.xltx
Macro-enabled template
.xltm
Non-XML binary workbook
.xlsb
Macro-enabled add-in
.xlam

PowerPoint

XML file type
Extension
Presentation
.pptx
Macro-enabled presentation
.pptm
Template
.potx
Macro-enabled template
.potm
Macro-enabled add-in
.ppam
Show
.ppsx
Macro-enabled show
.ppsm
Slide
.sldx
Macro-enabled slide
.sldm
Office theme
.thmx

Can different versions of Office share the same files?

Office lets you save files in the Open XML Formats and in the binary file format of earlier versions of Office and includes compatibility checkers and file converters to allow file-sharing between different versions of Office.

Opening existing files in Office You can open and work on a file that was created in an earlier version of Office, and then save it in its existing format. Because you might be working on a document with someone who uses an earlier version of Office, Office uses a compatibility checker that verifies that you have not introduced a feature that an earlier version of Office does not support. When you save the file, the compatibility checker reports those features to you and then lets you remove them before continuing with the save.