audio/gsm-efr is a audio media type.
Quick facts
What is audio/gsm-efr
audio/gsm-efr is one of the audio media types used on the internet. When serving this content over HTTP, set the Content-Type header in the response, for example:
Content-Type: audio/gsm-efr
Relation chain
Related MIME types
Used with
Related headers
Related methods
Frequently asked questions
audio/gsm-efr is a audio media type used to identify a content format; servers announce it to clients with the Content-Type header.
Extensions such as none registered are associated with this MIME type.
Send Content-Type: audio/gsm-efr in the HTTP response.
Sources & standards
Updated 2026-08-18
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