D Phrygian

The D Phrygian mode — D Eb F G A Bb C — shown across the guitar neck.

Swipe the neck sideways to see the higher frets.

D Phrygian is the natural minor with one note changed — the b2, Eb. That single note is what the mode sounds like; lean on it and the colour is obvious, avoid it and you are just playing minor.

The tool shows this from its parent key, Bb major, with D marked as where Phrygian begins, the same seven notes centered on Bb.