Harmonica et positions is a free extension designed for musicians and harmonica enthusiasts. With this extension, users can easily find the key of their harmonica based on a song's key and playing position, as well as find the key of a song based on the harmonica's key and playing position. The extension supports harmonicas tuned in C, Db, D, Eb, E, F, F#, G, Ab, A, Bb, and B.

The main features of Harmonica et positions include searching for the key of the harmonica corresponding to a given song key and playing position, searching for the song key corresponding to a given harmonica key and playing position, and support for a wide range of harmonica tunings. The interface is simple and user-friendly, making it a practical tool for musicians who want to play the harmonica in different keys and playing positions. Installing the extension on your Chrome browser is quick and easy, allowing you to start using it in just a few clicks.