One particular problem with MIDI files on the web is common enough to merit special attention. You may find that when you try to download a MIDI file from your web site, your browser does not recognize what type of file it is.

This can happen even though your browser understood the file when it was on your local hard drive.

Here’s what’s going on in this situation. Every time a web server sends out a resource such as a web page, MIDI file, or whatever, it first sends an HTTP header to tell what kind of information is being sent. For example, when a web page is sent, the MIME type is text/html. The MIME type for MIDI is audio/midi. The server usually (but not always) determines the data type of the file extension. The standard file extensions for MIDI are “.mid” and “.midi”.

However, if the server doesn’t recognize the extension, it won’t send the correct MIME type. This is very often the problem with MIDI files on the web. (It’s worth noting that this problem can actually happen with any type of media — it just seems to happen very frequently with MIDIs.)

MIDI has become popular with many people now using it on their web pages. However, the web servers of the world have not all caught up and are sending bad mime types. Fortunately, this is an easy problem to solve. If you are having problems getting MIDIs from your web server, send a note like this to your web server administrator:

Could you configure the web server so that the mime type for
file extensions .mid and .midi is
audio/midi? Thanks! 🙂

Adam is a technical writer who specializes in developer documentation and tutorials.