What is correct content-type for excel files?
excel, mime-types
Solution
For BIFF .xls files
application/vnd.ms-excel
For Excel2007 and above .xlsx files
application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
Problem
I want excel files on a website to open in Excel when clicked, not get saved on desktop, or get opened embedded in a browser etc. Now obviously it all depends on how everything is configured for each user, but what's the best Content-Type and other settings to achieve just that most of the time?