screenshot of Midiflip


MIDI music mayhem - flip, transpose, and arbitrarily remap pitches in MIDI files


MidiFlip is a software tool that allows users to transform MIDI songs and create mathematical remixes. Inspired by Andrew Huang's #MidiFlip challenge, MidiFlip gives users the ability to flip notes, invert pitches, and make arbitrary remappings. It offers both a web interface and a command-line interface for easy usage. With MidiFlip, users can batch convert files, download the results in a zip file, and have complete control over the notes in a simple way.

Key Features

  • MIDI Transformation: MidiFlip allows users to flip notes, invert pitches, and make arbitrary remappings of MIDI songs.
  • Web Interface: Users can access MidiFlip online, use the web interface, and enjoy all the functionalities that the command-line interface offers.
  • Batch Conversion: MidiFlip supports batch conversion of MIDI files, allowing users to process multiple files simultaneously.
  • Downloadable Results: Users can download the transformed MIDI files as a zip file, ensuring easy access and sharing.
  • CLI Installation: MidiFlip can be easily installed through Node.js and accessed through the command line.
  • CLI Usage: Users can utilize the command line to flip a single file or a bulk of files, providing flexibility in the transformation process.


To install MidiFlip, follow these steps:

  1. Install Node.js if you haven't already.
  2. Open a terminal or command prompt.
  3. Run the following command:
    npm install midiflip -g
  4. You should now have access to the midiflip command.


MidiFlip is a versatile tool that empowers users to transform MIDI songs and create unique mathematical remixes. With its ability to flip notes, invert pitches, and make arbitrary remappings, MidiFlip offers users complete control over their MIDI compositions. Whether using the web interface or the command-line interface, users can conveniently batch convert files, download the results, and explore various transformation options. With its potential future directions, such as transposing notes, altering tempo and durations, and handling pitch bends and portamenti, MidiFlip provides endless possibilities for musical experimentation.


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