/Web APIs


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The MIDIMessageEvent interface of the Web MIDI API represents the event passed to the midimessage event of the MIDIInput interface. A midimessage event is fired every time a MIDI message is sent from a device represented by a MIDIInput, for example when a MIDI keyboard key is pressed, a knob is tweaked, or a slider is moved.

Event MIDIMessageEvent



Creates a new MIDIMessageEvent object instance.

Instance properties

This interface also inherits properties from Event.


A Uint8Array containing the data bytes of a single MIDI message. See the MIDI specification for more information on its form.

Instance methods

This interface doesn't implement any specific methods, but inherits methods from Event.


The following example prints all MIDI messages to the console.

navigator.requestMIDIAccess().then((midiAccess) => {
  Array.from(midiAccess.inputs).forEach((input) => {
    input[1].onmidimessage = (msg) => {


Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
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MIDIMessageEvent 43 79 10897–108 No 30 No No 43 No 30 No 4.0
data 43 79 10897–108 No 30 No No 43 No 30 No 4.0

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