Guitar Sharps, Flats & Natural Signs Explained
The seven natural notes A-G only cover part of the fingerboard. Sharps and flats fill in the gaps - and once you understand them, the entire guitar neck opens up.
The seven natural notes A-G only cover part of the fingerboard. Sharps and flats fill in the gaps - and once you understand them, the entire guitar neck opens up.
The seven natural notes - A, B, C, D, E, F, G - cover most of the fingerboard, but not all of it. Between most pairs of natural notes there is a gap: an extra fret that has no natural letter name. These unnamed positions are the sharps and flats.
There are two important exceptions: there is no sharp or flat between B and C, or between E and F. These pairs are already only one fret apart - a semitone - so there is no room for a note between them.
B → C: no sharp or flat between them. They are already one fret apart.
E → F: same - one fret apart, no gap.
Between every other pair of natural notes (A-B, C-D, D-E, F-G, G-A) there is one fret gap containing a sharp or flat note.
A sharp note is one fret position higher than the natural note with the same letter name. The sharp sign looks like a hash: #
On the stave, a sharp sign appears immediately before the note head it applies to. On the guitar, simply play the same string one fret higher than the natural note.
Every sharp note is exactly one fret higher than its natural counterpart on the same string. F sharp on the 1st string is at fret 2 (F natural is at fret 1). G sharp on the 1st string is at fret 4 (G natural is at fret 3).
A flat note is one fret position lower than the natural note with the same letter name. The flat sign looks like a lowercase b: b
On the stave, a flat sign appears immediately before the note head. On the guitar, play the same string one fret lower. If the natural note is an open string, move to the next lower fret on the same string.
When a sharp or flat sign appears before a note on the stave, it affects:
It does not carry over into the next bar - the effect is automatically cancelled by the next bar line.
If a sharp or flat appears earlier in a bar and you need the natural version of that note in the same bar, a natural sign (♮) is placed before it. The natural sign cancels the sharp or flat for the rest of that bar only.
The musical alphabet has only seven natural notes: A, B, C, D, E, F, and G. After G, it starts again at A. Between most of these notes there is a gap of one semitone (one fret on the guitar) called a sharp or flat. A sharp (#) raises a note by one semitone, while a flat (b) lowers it by one semitone. So the note between C and D can be called either C# (C sharp) or Db (D flat), depending on the musical context.
Importantly, not every pair of natural notes has a gap between them. Between B and C, and between E and F, there is no gap. These pairs are natural semitones, which is why there is no B#, no Cb (in practical terms), no E#, and no Fb used in everyday music. Understanding this pattern is one of the most important building blocks in music theory.
On the guitar, moving one fret up (toward the body) raises the pitch by one semitone, which is one sharp. Moving one fret down (toward the headstock) lowers the pitch by one semitone, which is one flat. This means that every fret position on the guitar is either a natural note (A, B, C, D, E, F, or G) or a sharp/flat note, and knowing which is which at any given fret is the foundation of fretboard navigation.
On the low E string, the notes in order from the open string are: E, F, F#/Gb, G, G#/Ab, A, A#/Bb, B, C, C#/Db, D, D#/Eb, and then back to E at the 12th fret (one octave higher). Every string follows this same sequence of notes, just starting from a different open string pitch. Once you learn this pattern on one string, you know it for every string.
When the same pitch has two different names (like F# and Gb), those names are called enharmonic equivalents. They represent the exact same fret on the guitar, the exact same piano key, the exact same frequency of vibration. The note sounds identical. The different names exist purely for notational clarity in different musical keys.
In the key of G major, you will always see F# written, never Gb. In the key of Db major, you will see Gb written, never F#. The choice of name depends on which makes the key signature easiest to read. For guitarists playing by ear or by tab, this distinction rarely matters. It becomes important when you start reading sheet music or communicating with other musicians who read notation.
A key signature is a set of sharps or flats that applies to every note of that name throughout a piece of music. If a song is in the key of D major, it has a key signature of two sharps: F# and C#. This means every F and every C in the piece is automatically sharp unless specifically marked as natural. Rather than writing a sharp symbol before every F and C, composers write the sharps once at the start of each line.
For guitarists, understanding key signatures helps you predict which notes will sound in tune together. The key of G has one sharp (F#). The key of D has two sharps (F# and C#). The key of A has three (F#, C#, G#). Each time you add a sharp, you move to the key a fifth higher. This circular relationship between keys is called the circle of fifths and it is one of the most powerful maps in all of music theory.
Even if you never read sheet music, understanding sharps and flats helps you in several practical ways. It lets you understand why certain strings need to be avoided when playing in certain keys. It helps you figure out which scale to improvise over a song. It lets you transpose a song from one key to another by counting frets. And it lets you communicate with other musicians clearly, whether they play guitar, piano, or any other instrument.
Before memorising where the sharps and flats are on the fretboard, first memorise where all the natural notes (A, B, C, D, E, F, G) are on just the low E string. Once you know those seven positions, finding the sharp between any two of them is simple: it is always the fret directly between them. This "anchor on naturals" approach is the fastest way to build fretboard knowledge.
You might be wondering: if I move one fret up from C, it's C-sharp (C#). But if I move one fret down from D, it's D-flat (Db). Are C# and Db the same note? Yes! On a guitar, they are the exact same fret and produce the exact same sound.
This concept is called an Enharmonic Equivalent. Whether a musician calls that fret C# or Db simply depends on the "Key Signature" of the song they are playing. For now, just remember that they share the exact same space on your fretboard.
Everything you need to know about this lesson
In the standard musical alphabet, the intervals between E/F and B/C are naturally half-steps. Since there is no physical fret between them, they don't have a sharp/flat between them.
A natural note is just the plain letter name without a sharp or flat attached (like A, B, C). On sheet music, a natural sign cancels out a previous sharp or flat.
A sharp raises the pitch by one half-step (one fret up the neck, toward the body). A flat lowers the pitch by one half-step (one fret down, toward the headstock).
It depends on the key of the song! Guitar players naturally lean towards thinking in sharps (because keys like G, D, and A use them heavily), while horn players often think in flats.
A double sharp raises a natural note by two half-steps (one whole step). For example, C double sharp is the exact same pitch as D.
They are necessary in music theory to maintain the strict alphabetical order of scales in complex key signatures without repeating letter names.
Don't try to memorize them all at once! Learn the natural notes (A, B, C, D, E, F, G) first. The sharps and flats are simply the gaps between them.
An accidental is a sharp, flat, or natural symbol that appears in the middle of a measure, temporarily altering a note outside of the song's main key signature.
Standard guitars are fretted in half-steps (semitones). To play notes 'between' the frets (microtones), you have to physically bend the string!
Technically yes, your open E string is now an Eb. However, most guitarists still read tabs and chords as if they are in standard tuning to make it easier to read.