Mime type for WOFF fonts?

Question

What mime type should WOFF fonts be served as?

I am serving truetype (ttf) fonts as font/truetype and opentype (otf) as font/opentype, but I cannot find the correct format for WOFF fonts.

I have tried font/woff, font/webopen, and font/webopentype, but Chrome still complains:

"Resource interpreted as font but transferred with MIME type application/octet-stream."

Anybody know?

Answer 1

Update from Keith Shaw's comment on Jun 22, 2017:

As of February 2017, RFC8081 is the proposed standard. It defines a top-level media type for fonts, therefore the standard media type for WOFF and WOFF2 are as follows:

font/woff

font/woff2

---

In January 2011 it was announced that in the meantime Chromium will recognize

application/x-font-woff

as the mime-type for WOFF. I know this change is now in Chrome beta and if not in stable yet, it shouldn't be too far away.

Answer 2

For me, the next has beeen working in an .htaccess file.

AddType font/ttf .ttf
AddType font/eot .eot
AddType font/otf .otf
AddType font/woff .woff
AddType font/woff2 .woff2   

Answer 3

It will be application/font-woff.

see http://www.w3.org/TR/WOFF/#appendix-b (W3C Candidate Recommendation 04 August 2011)

and http://www.w3.org/2002/06/registering-mediatype.html

From Mozilla css font-face notes

In Gecko, web fonts are subject to the same domain restriction (font files must be on the same domain as the page using them), unless HTTP access controls are used to relax this restriction. Note: Because there are no defined MIME types for TrueType, OpenType, and WOFF fonts, the MIME type of the file specified is not considered.

source: https://developer.mozilla.org/en/CSS/@font-face#Notes

Answer 4

Reference for adding font mime types to .NET/IIS

via web.config

<system.webServer>
  <staticContent>
     <!-- remove first in case they are defined in IIS already, which would cause a runtime error -->
     <remove fileExtension=".woff" />
     <remove fileExtension=".woff2" />
     <mimeMap fileExtension=".woff" mimeType="font/woff" />
     <mimeMap fileExtension=".woff2" mimeType="font/woff2" />
  </staticContent>
</system.webServer>

via IIS Manager