A comprehensive list of all known MIME types can be found here.

File extension File type MIME type

.docx

Microsoft Office Word 2007 document

application/vnd.openxmlformats-officedocument.wordprocessingml.document

.docm

Office Word 2007 macro-enabled document

application/vnd.ms-word.document.macroEnabled.12

.dotx

Office Word 2007 template

application/vnd.openxmlformats-officedocument.wordprocessingml.template

.dotm

Office Word 2007 macro-enabled document template

application/vnd.ms-word.template.macroEnabled.12

.xlsx

Microsoft Office Excel 2007 workbook

application/vnd.openxmlformats-officedocument.spreadsheetml.sheet

.xlsm

Office Excel 2007 macro-enabled workbook

application/vnd.ms-excel.sheet.macroEnabled.12

.xltx

Office Excel 2007 template

application/vnd.openxmlformats-officedocument.spreadsheetml.template

.xltm

Office Excel 2007 macro-enabled workbook template

application/vnd.ms-excel.template.macroEnabled.12

.xlsb

Office Excel 2007 binary workbook

application/vnd.ms-excel.sheet.binary.macroEnabled.12

.xlam

Office Excel 2007 add-in

application/vnd.ms-excel.addin.macroEnabled.12

.pptx

Microsoft Office PowerPoint 2007 presentation

application/vnd.openxmlformats-officedocument.presentationml.presentation

.pptm

Office PowerPoint 2007 macro-enabled presentation

application/vnd.ms-powerpoint.presentation.macroEnabled.12

.ppsx

Office PowerPoint 2007 slide show

application/vnd.openxmlformats-officedocument.presentationml.slideshow

.ppsm

Office PowerPoint 2007 macro-enabled slide show

application/vnd.ms-powerpoint.slideshow.macroEnabled.12

.potx

Office PowerPoint 2007 template

application/vnd.openxmlformats-officedocument.presentationml.template

.potm

Office PowerPoint 2007 macro-enabled presentation template

application/vnd.ms-powerpoint.template.macroEnabled.12

.ppam

Office PowerPoint 2007 add-in

application/vnd.ms-powerpoint.addin.macroEnabled.12

.sldx

Office PowerPoint 2007 slide

application/vnd.openxmlformats-officedocument.presentationml.slide

.sldm

Office PowerPoint 2007 macro-enabled slide

application/vnd.ms-powerpoint.slide.macroEnabled.12

.one

Microsoft Office OneNote 2007 section

application/msonenote

.onetoc2

Office OneNote 2007 TOC

application/msonenote

.onetmp

Office OneNote 2007 temporary file

application/msonenote

.onepkg

Office OneNote 2007 package

application/msonenote

.thmx

2007 Office system release theme

application/vnd.ms-officetheme