Fully Open-sourced Online MIDI Editor

Start making music without installing anything


Supported desktop browsers: Google Chrome / Firefox / Safari


Fully equipped MIDI editor
Orchestrate freely with the multi-track piano roll editor. Of course, you can use velocity, pitch bend, expression, and modulation to create expressive sound.
GM compatible sound module
128 virtual instruments loaded at very high speed. A dedicated sound module built with the WebAudio API and AudioWorklet allows you to play countless notes in your browser.
Ultra-fast audio file export
You can save the music you create as a WAV file and listen to it on your smartphone, use it as background music for your videos, or import it into your DAW.
MIDI I/O Support
Using a browser that supports the Web MIDI API, you can record the performance of a MIDI keyboard connected to your computer, or play sounds from a hardware synth.
Non-4/4 time signature and 300+ bpm
The graph editor allows you to freely change the tempo and time signature in the middle of a song.
PWA Support
Want to hide your browser's address bar? You can install it on your desktop and use it as an application.


@signalmidi Check for updates on Twitter
ryohey/signal Report bugs or Request features on GitHub