A symbol that raises a note by one semitone, used in key signatures and as an accidental to alter pitch within a measure.
A sharp (♯) is a musical symbol that raises a pitch by one semitone (half step). It appears in two main contexts: in a key signature, where it defines which notes are consistently raised throughout a piece, and as an accidental placed before a specific note to alter that pitch within a measure. Together with flats (♭) and naturals (♮), sharps are essential tools for chromatic harmony and modulation.
On the staff, the sharp symbol resembles a hash or number sign and is written immediately to the left of the notehead it affects (or at the start of each staff line in a key signature). A single sharp raises the note once; double sharps (♯♯) raise it by two semitones, though these are less common in beginner repertoire.
Musically, applying a sharp means moving one key to the right on the piano—or lengthening the vibrating length on string instruments, or adjusting fingering on wind instruments—to produce a higher frequency. The interval between a natural note and its sharped version is always a minor second (one semitone).
Key signatures use sharps in a fixed order: F♯, C♯, G♯, D♯, A♯, E♯, B♯. This sequence follows the circle of fifths moving toward sharp keys (G major has one sharp, D major has two, and so on). Understanding this order helps musicians read signatures quickly and predict which notes will be altered.
The opposite alteration is the flat (♭), which lowers pitch by a semitone. The natural (♮) cancels a previous sharp or flat within the same measure, restoring the note to its diatonic form in the current key.
Sharps appear in virtually every genre. In classical music, sharp keys such as A major and E major are favored for their bright, open color—think of violin concertos, fanfares, and much Baroque string writing. Jazz and contemporary music use raised scale degrees and chromatic passing tones with sharps to add tension and forward motion. Pop and rock often borrow chords with sharped roots or thirds for harmonic lift.
Accidentals with sharps are common when composers modulate upward by fifths, introduce leading tones, or heighten expressive intensity before resolution. Reading fluently requires recognizing both the key signature sharps and any additional accidentals on the page.
When learning sharps, start by naming the affected notes aloud: “F becomes F♯,” “C becomes C♯.” On piano, play the white key and its right neighbor to internalize the semitone rise. For reading, drill key signatures separately from accidentals—know how many sharps are in each key before you play the piece.
On string and wind instruments, practice the physical adjustment for each sharp until intonation is steady. In ensemble playing, match pitch with others when a passage introduces accidental sharps outside the key signature. When you see a natural (♮) after a sharp in the same measure, return to the unaltered pitch unless the composer marks otherwise.