.weba MIME type
WebM audioaudio
audio/webmAudio-only WebM, usually with Opus inside. Recordings are often saved as .webm even when they have no video.
| MIME type | audio/webm |
|---|---|
| Extensions | .weba |
| Content-Type | audio/webm |
| Compress in transit? | No — already compressed |
| File signature | 1A 45 DF A3 the EBML header shared by WebM and Matroska |
Good to know
- Chromium's MediaRecorder records audio as
audio/webm;codecs=opusby default, while Safari has historically recorded MP4. CheckMediaRecorder.isTypeSupported()rather than assuming a type. - When you upload a recording, send the Blob's own
typeas the Content-Type instead of hard-coding one.
Serve .weba files with the right type
The response header to send:
Content-Type: audio/webm
Most servers pick the type from the file extension. If yours sends the wrong one, map it explicitly:
nginx (inside the types block in mime.types)
audio/webm weba;
Apache (.htaccess or server config)
AddType audio/webm .weba
Express
res.set("Content-Type", "audio/webm");Python
import mimetypes
mimetypes.add_type("audio/webm", ".weba")HTML file input
<input type="file" accept=".weba,audio/webm">
Check it
See what a server sends for a file, and what type a local file really is by its contents:
curl -sI https://example.com/file.weba | grep -i '^content-type:' file --mime-type file.weba
Frequently asked questions
What is the MIME type for .weba files?
audio/webm.
What Content-Type header should a .weba file be served with?
Content-Type: audio/webm. It's already compressed, so servers shouldn't gzip it.
How can I tell if a file is really a .weba?
Check its bytes rather than the extension: WEBA files start with 1A 45 DF A3 — the EBML header shared by WebM and Matroska. On the command line, file --mime-type name.weba does this for you.
Related types
Headers that go with it: Content-Type · Content-Disposition · X-Content-Type-Options