A free collection of midi responsive widgets made for musicians, teachers, and students.

Fill in the gaps of your music theory knowledge, enhance your creative process, communicate musical ideas efficiently, and create your own templates/tutorials.

How it works


How to use Midi Sandbox to practice with a midi controller.

How to use your own midi files with the new Midi File Player.


This template contains a modified excerpt from the song Feather by Nujabes. A good beginner exercise for changing keys. See the tutorial above for some tips on how to practice.

Includes the sheet music for Avril 14th by Aphex Twin along with some other common widgets. Feel free to customize it and create your own template!

Includes the sheet music for Nana Theme by Holland Patent Public Library. Check out their solo work if you like the Joe Pera Talks With You soundtrack.



A basic, but important tool for visualizing the notes being played. Great for training yourself to stop staring at your hands while playing.

Chord Estimator

Figure out the names of the chords you’re playing instantly. Don’t forget to change your Key setting to get the best estimates.

Circle of Fifths

One of the most useful tools in all of music theory. Use it as a reference, or toggle the Key Prevalence setting to highlight the keys that match the notes you’re playing.

Sheet Music

Upload your own MusicXML files and take advantage of the playback features, or toggle the setting to iterate the cursor when you play the correct notes.


Visualize the note’s you’re playing on a grand staff. Useful for beginners, or anyone learning new sheet music.


Connect the dots of music theory and gain a deeper understanding of harmony. Master this tool and you’ll be able to construct chords in any context instantly.

Midi File Player

Upload your own midi files to use as input instead of a midi controller. Optionally, add an audio file to sync with the midi file via standard playback controls.

Youtube Player

Easily embed youtube videos and customize the layout in your templates. Optionally, sync the playback with a Midi File Player and/or Sheet Music widget.

tonnetz mesh

The Tonnetz is a 2-dimensional mesh that illustrates spacial representations of tonal distance and relationships. Think of it as adding another dimension to the Circle of Fifths. In fact, if you start on any note and continue down the right path you are essentially going around the Circle of Fifths. Similarly, each branch off of a note represents a different interval (bottom right – major 3rd, top right – minor 3rd, etc).

Check out this article by Josh Walsh for an excellent breakdown of what you can learn from the Tonnetz.


Create a free account to upload your own MusicXML and Midi files.


Send me a message if you:

  1. Have feedback on how to improve Midi Sandbox. 
  2. Are interested in contributing to Midi Sandbox as a designer.
  3. Still have questions after reading the FAQ page.

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