Interactive Guitar Fretboard, Chords & Scales Tool

This is the home screen of the ThunderFret tool: a full 24-fret guitar neck mirrored by a piano keyboard, where every note you tap is played aloud and lit in every octave. Tap notes to build your own selections and the tool names what you have built — pick out three notes of a chord and it will tell you which chord they spell. Everything is colored by interval, so the distance from the root is something you see, not just count.

The same board powers every other section: switch to Scale or Chord mode from the strip above the neck, change the root, swap to bass or ukulele, turn on the capo, or go left-handed. All of it is free with no account — the tool ships with every chord type, every tuning and every scale unlocked. When you want the why behind what you see, the theory guides below explain each concept in plain English and deep-link straight back into the board.