A sign changes the pitch
A sharp (♯) raises a note by one semitone. A flat (♭) lowers it by one semitone. A natural sign (♮) cancels an alteration in the relevant musical context. On a guitar, one fret equals one semitone, so F♯ is one fret above F and G♭ is one fret below G.
There is already just one semitone between E and F, and between B and C. The other neighboring natural letter names are separated by two semitones. That is why the distance between natural notes is not always the same number of frets.
One sound, different spellings
In the equal-tempered tuning used by this trainer, F♯ and G♭ sound the same. They are enharmonic spellings. Their names describe different relationships in written music, so do not assume the spellings are interchangeable in every score.
Choose natural notes, sharps or flats in the app. Sharps and flats modes include natural notes as well. The notation and answer labels follow the selected spelling. In a real score, also read the key signature and the rules for accidentals within a measure; the app’s isolated notes do not teach those rules in full.
Try it yourself
What is another name for the F♯ at string 1, fret 2?
Show the answer
G♭. It is a semitone above F at fret 1 and a semitone below G at fret 3.