Media type / application
application/vnd.ms-excel
Legacy binary Excel workbooks (.xls), still produced by older reporting and finance tooling.
Served inline: Browsers have no renderer for this, so it downloads even without a Content-Disposition header. That makes it the quiet default for anything you do not want opened in place.
Browser behaviour
Downloads
Charset
no charset
Compression
Already compressed
Send it like this
Content-Type: application/vnd.ms-excelA binary payload has no character encoding. A charset parameter here is meaningless and occasionally confuses strict parsers.
Handling verdict
Browsers have no renderer for this, so it downloads even without a Content-Disposition header. That makes it the quiet default for anything you do not want opened in place.
A binary payload has no character encoding. A charset parameter here is meaningless and occasionally confuses strict parsers.
The format compresses internally. Another transport encoding costs CPU on both ends and typically changes the size by less than a percent — sometimes upward.
A `vnd.` subtype belongs to a specific product or organisation. It is registered, but its meaning is defined by that vendor rather than by a standards body.
Anatomy of the name
RFC 6838Top-level type
application
Application
Subtype
vnd.ms-excel
Registered in the vendor tree.
Structured syntax
none
No suffix, so the payload format is defined entirely by the subtype itself.
Parameters
none
Beyond the charset rule above, this type defines no parameters of its own.
Response headers
Content-Type: application/vnd.ms-excel
X-Content-Type-Options: nosniff
Content-Disposition: attachment; filename="example.xls"nosniff stops the browser second-guessing the type you declared, which is what makes the rest of this reliable. Content-Disposition: attachment names the saved file and removes any doubt about rendering.
Server configuration
extension mappingnginx
types {
application/vnd.ms-excel xls xlm xla;
}Apache
AddType application/vnd.ms-excel .xls .xlm .xlaCaddy
@type path *.xls *.xlm *.xla
header @type Content-Type "application/vnd.ms-excel"