Missing MIME types for Excel Workbooks ('.xlsx') files

Ideas
1

There are already MIME types for ‘.xls’ and ‘.xlb’ within the type_map dictionary in the mimetype library. Why don’t we add the other excel formats??

.xlsx     application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
.xltx     application/vnd.openxmlformats-officedocument.spreadsheetml.template
.xlsm     application/vnd.ms-excel.sheet.macroEnabled.12
.xltm     application/vnd.ms-excel.template.macroEnabled.12
.xlam     application/vnd.ms-excel.addin.macroEnabled.12
.xlsb     application/vnd.ms-excel.sheet.binary.macroEnabled.12
2

Which operating system (OS) and version are you using?
On linux for example the mime types are loaded from OS files.

3

When I work in docker containers I have to manually add them most of the time.

4

I added about 50 MIME types to Python 3.14, including for .docx , .pptx and .xlsx, but not those other .xl** ones:

The .***x ones are defined in ECMA-376, are the .xl** defined there too, or in another standard? (I’m on mobile right now, so it’s hard to search zipped PDFs.)

3 Likes
5

I found them in the official office documentation, but will checkout those ECMA files to give you a better answer.