.mp3 MIME Type — audio/mpeg

Q: How do I set the Content-Type for .mp3 in Nginx?

Make sure audio/mpeg mp3; is listed in the types block (usually in /etc/nginx/mime.types) and reload Nginx.

audio/mpeg

MIME type for .mp3

Audio

What is the MIME type of .mp3 files?

The MIME type (media type) for MP3 audio files with the .mp3 extension is audio/mpeg. The type is audio/mpeg; audio/mp3 is unofficial but widely accepted.

Content-Type header

Content-Type: audio/mpeg

Server configuration

Server	Configuration
Nginx (`mime.types` or `types {}`)	`audio/mpeg mp3;`
Apache (`.htaccess`)	`AddType audio/mpeg .mp3`
IIS (`web.config`)	`<mimeMap fileExtension=".mp3" mimeType="audio/mpeg" />`
Node.js / Express	`res.type('mp3')` or `res.setHeader('Content-Type', 'audio/mpeg')`
Amazon S3	Set `Content-Type: audio/mpeg` on the object (metadata), or pass `--content-type audio/mpeg` to `aws s3 cp`

Should .mp3 files be compressed?

No. MP3 audio files are already compressed internally, so gzip or Brotli would waste CPU and barely reduce — sometimes even increase — the size. Leave audio/mpeg out of your compression configuration.

Why the MIME type matters

Browsers decide what to do with a response — render, run, play or download — from the Content-Type header, not the file extension. With X-Content-Type-Options: nosniff, a wrong type causes stylesheets and scripts to be blocked outright. For uploads, never trust the type sent by the client; check the file’s content (its magic bytes) on the server.

Frequently asked questions

What is the MIME type for .mp3?

audio/mpeg.

How do I set the Content-Type for .mp3 in Nginx?

Make sure audio/mpeg mp3; is listed in the types block (usually in /etc/nginx/mime.types) and reload Nginx.

Should I gzip .mp3 files?

No — the format is already compressed, so HTTP compression gives no benefit.

.mp3 MIME Type: audio/mpeg