diff --git a/midi/midi-tests.ts b/midi/midi-tests.ts
new file mode 100644
index 0000000000..cf8566f7fb
--- /dev/null
+++ b/midi/midi-tests.ts
@@ -0,0 +1,69 @@
+/// <reference path="midi.d.ts" />
+/// <reference path="../es6-promise/es6-promise.d.ts" />
+
+if (navigator.requestMIDIAccess !== undefined) {
+    navigator.requestMIDIAccess().then(onSuccessCallback, onErrorCallback);
+}
+
+var onSuccessCallback = (item: Midi.MIDIAccess)=>{
+    this._midiPort = item;
+
+    item.onconnect = (event: Midi.MIDIConnectionEvent)=>{
+        console.log("onconnect");
+        console.log(event);
+    };
+
+    item.ondisconnect = (event: Midi.MIDIConnectionEvent)=>{
+        console.log("ondisconnect");
+        console.log(event);
+    };
+
+    console.log("sysexenabled");
+    console.log(item.sysexEnabled);
+
+    /*
+     console.log(item.inputs.get("701435409"));
+     console.log(item.inputs.has("701435409"));
+     console.log(item.inputs.keys());
+     console.log(item.inputs.keys().next());
+     console.log(item.inputs.values());
+     var inputs = this._midiPort.inputs.values();
+     console.log(this._midiPort.inputs.entries().next());
+     console.log(this._midiPort.inputs.entries().next().done);
+     */
+
+    var inputs = this._midiPort.inputs.values();
+
+    /*
+     console.log(item.outputs.get("384570428"));
+     console.log(item.outputs.has("384570428"));
+     console.log(item.outputs.keys());
+     console.log(item.outputs.keys().next());
+     console.log(item.outputs.values());
+     console.log(this._midiPort.outputs.entries().next());
+     console.log(this._midiPort.outputs.entries().next().done);
+     */
+
+    for(var o = inputs.next(); !o.done; o = inputs.next()){
+        this._inputs.push(o.value);
+        console.log(o.value);
+    }
+
+    var outputs = item.outputs.values();
+    for(var op = outputs.next(); !op.done; op = outputs.next()){
+        this._outputs.push(op.value);
+        op.value.send([ 0x90, 0x45, 0x7f ] );
+    }
+
+    for(var cnt = 0; cnt < this._inputs.length; cnt++){
+        this._inputs[cnt].onmidimessage = (event: Midi.MIDIMessageEvent)=>{
+            this.onMidiMessage(event.data);
+        };
+    }
+};
+
+var onErrorCallback = (access: Error)=>{ };
+
+var onMidiMessage = (event: Uint8Array)=>{
+    console.log(event);
+};
\ No newline at end of file
diff --git a/midi/midi.d.ts b/midi/midi.d.ts
new file mode 100644
index 0000000000..59250c3e4a
--- /dev/null
+++ b/midi/midi.d.ts
@@ -0,0 +1,131 @@
+// Type definitions for Web MIDI API
+// Project: http://www.w3.org/TR/webmidi/
+// Definitions by: Toshiya Nakakura <https://github.com/nakakura>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+/// <reference path="../es6-promise/es6-promise.d.ts" />
+
+interface Navigator {
+    /**
+     * When invoked, returns a Promise object representing a request for access to MIDI devices on the user's system.
+     * @param options settings that may be provided to the requestMIDIAccess request.
+     */
+    requestMIDIAccess (options?: Midi.MidiOptions): Promise<Midi.MIDIAccess>;
+}
+
+declare module Midi{
+    /**
+     * optional settings that may be provided to the requestMIDIAccess request.
+     */
+    export interface MidiOptions{
+        sysex: boolean;
+    }
+
+    export interface IteratorItem<S>{
+        value: S;
+        done: boolean;
+    }
+
+    export interface Iterator<S>{
+        next(): IteratorItem<S>;
+    }
+
+    interface Tuple2<A,B> {
+        fst: A
+        snd: B
+    }
+
+    /**
+     * This type is used to represent all the currently available MIDI input ports as a MapClass-like interface
+     */
+    export interface MIDIInputMap{
+        size: number;
+        keys: ()=>Iterator<string>;
+        entries: ()=>Iterator<Tuple2<string, MIDIInput>>;
+        values(): Iterator<MIDIInput>;
+        get(key: string): MIDIInput;
+        has(key: string): boolean;
+    }
+
+    /**
+     * This type is used to represent all the currently available MIDI output ports as a MapClass-like interface.
+     */
+    export interface MIDIOutputMap{
+        size: number;
+        keys: ()=>Iterator<string>;
+        entries: ()=>Iterator<Tuple2<string, MIDIOutput>>;
+        values(): Iterator<MIDIOutput>;
+        get(key: string): MIDIOutput;
+        has(key: string): boolean;
+    }
+
+    /**
+     * This interface provides the methods to list MIDI input and output devices, and obtain access to an individual device.
+     */
+    export interface MIDIAccess extends EventTarget{
+        inputs: MIDIInputMap;
+        outputs: MIDIOutputMap;
+        onconnect: (event: MIDIConnectionEvent)=>void;
+        ondisconnect: (event: MIDIConnectionEvent)=>void;
+        sysexEnabled: boolean;
+    }
+
+    /**
+     * This interface represents a MIDI input or output port.
+     */
+    export enum MIDIPortType{
+        input,
+        output
+    }
+
+    /**
+     * This interface represents a MIDI input or output port.
+     */
+    export interface MIDIPort extends EventTarget {
+        id: string;
+        manufacture?: string;
+        name?: string;
+        type: MIDIPortType;
+        version?: string;
+        ondisconnect: Function;
+    }
+
+    /**
+     * Interface for midi inputs
+     */
+    export interface MIDIInput{
+        onmidimessage: (event: MIDIMessageEvent)=>void;
+    }
+
+    /**
+     * Interface for midi outputs
+     */
+    export interface MIDIOutput{
+        send(data: Array<number>, timestamp?: number): void;
+    }
+
+    /**
+     * An event object implementing this interface is passed to a MIDIInput's onmidimessage handler when MIDI messages are received.
+     */
+    export interface MIDIMessageEvent extends Event{
+        receivedTime: number;
+        data: Uint8Array;
+    }
+
+    export interface MIDIMessageEventInit{
+        receivedTime: number;
+        data: Uint8Array;
+    }
+
+    /**
+     * An event object implementing this interface is passed to a MIDIAccess' ondisconnect handler
+     */
+    export interface MIDIConnectionEvent extends Event{
+        port: MIDIPort;
+    }
+
+    export interface MIDIConnectionEventInit{
+        port: MIDIPort;
+    }
+}
+