Guitar Theory
How to Read a Fretboard Diagram
A fretboard diagram is a map of the guitar neck. Once you know how to read one, you can look up any scale, chord, or note pattern and immediately understand where to put your fingers.
The basic layout
A fretboard diagram shows the guitar neck from the front, as if you are looking at it while playing. The diagram is oriented horizontally. The thickest string (low E) is at the top or bottom depending on the source, but on Scaled it sits at the left side of the neck when viewed in standard orientation.
The vertical lines are frets. The horizontal lines are strings. The numbers along the top or bottom tell you which fret you are looking at. Fret 0 is the open string. Fret 12 is the octave, where the same notes repeat one octave higher.
Strings
A standard guitar has 6 strings. From thickest (lowest pitch) to thinnest (highest pitch), they are tuned to E, A, D, G, B, E. The thickest string is called the low E string. The thinnest is called the high E string.
When a diagram shows a note on the 5th string at fret 3, that means you press down the A string at the 3rd fret. The open note of the A string is A. Three frets up from A is C. So that position plays a C.
Frets and fret markers
The frets are the metal strips embedded in the neck. Pressing a string behind a fret (between two fret strips) raises the pitch. Each fret raises the pitch by one semitone, which is the smallest interval in western music.
Most guitars have dot markers on the fretboard at frets 3, 5, 7, 9, and 12. Fret 12 usually has a double dot. These are navigation markers, not musical indicators. They just help you find your place on the neck quickly.
Dots on the diagram
Filled circles on a fretboard diagram mark the notes you play. The color of the dot usually carries meaning. On Scaled, the root note of a scale is highlighted differently from the other scale notes so you can always find your tonal center at a glance.
When a diagram shows dots across multiple strings at similar frets, that is a scale position or shape. You are not expected to play all those notes at once. They show you which notes are available in that region of the neck so you can move between them when playing or improvising.
Open strings and the nut
The thick vertical line at the far left of a diagram (when it appears) represents the nut, which is the piece at the top of the neck where the strings rest before reaching the tuning pegs. When you see a dot on string at fret 0, that is an open string, meaning you pick or strum it without fretting any note. Open strings are common in chord diagrams.
When a diagram starts at fret 5 or fret 9, there is no nut shown. A number label tells you which fret the diagram begins at. This lets diagrams zoom in on any position of the neck without needing to show the whole thing from the open strings.
Full-neck vs. position diagrams
Some diagrams show the entire neck from fret 0 to fret 12 or 24. These give you a complete picture of where every note in a scale appears. Others show a single position, which is a cluster of notes within a 4-5 fret window that forms a playable shape.
Position diagrams are more common in beginner resources because they are easier to memorize and immediately playable. Full-neck diagrams are more useful for understanding the instrument as a whole. The Scale Mapper on Scaled shows the full neck so you can see every occurrence of every scale note at once.
See the full neck in action
Load any scale and explore every note across all 24 frets. Color-coded roots, interactive note labels, and diatonic triads built in.
Open Scale Mapper →