Question

I’m using @font-face for embedded fonts (thanks Paul Irish). In trying to fix Chrome’s warning about wrong MIME type for woff fonts, I’ve discovered a mass of conflicting suggestions.

Everyone seems to agree that .eot fonts (for IE 6-8?) should be served using

AddType application/vnd.ms-fontobject .eot

For .ttf fonts (older non-IE browsers?) I’ve seen

AddType application/x-font-ttf        .ttf
AddType application/octet-stream      .ttf
AddType font/truetype                 .ttf
AddType font/ttf                      .ttf

And for .woff fonts (the new standard?) I’ve seen

AddType application/font-wof          .woff
AddType application/x-font-woff       .woff
AddType application/x-woff            .woff

I understand the correct MIME type for woff will be application/font-woff, but until the standard is official, application/x-font-woff is understood by Chrome.

I realise I’ve half answered my question in asking it, but the question is really: is there any authoritative guidance or further advice about what MIME types should be used for fonts?

Update (in case it’s of any help to anyone else): since there seems to be nothing authoritative, I’ve settled on using the following font MIME types in my .htaccess (which at least keeps Chrome happy):

AddType application/vnd.ms-fontobject .eot
AddType application/x-font-ttf        .ttf
AddType application/x-font-woff       .woff

Answer 1

Usually, MIME types come from RFC.
You have a exhaustive list on the IANA site but none refers to the font extensions.
Moreover, document describing WOFF format is draft and does not refer to the mime type to use.
No reliable reference on the subject seems to exist for now.

Update

The W3C has now released WOFF as a recommendation, and in Appendix B defined the MIME type as application/font-woff. It’s also been added to the IANA site that you mentioned now. -GKFX