Accidental (music)

An accidental is a symbol modifying a note's pitch. There are three main types of accidentals:

Sharps (♯) raise a note's pitch by one semitone. For example, a sharp symbol on a D note indicates that the note should be played a semitone higher.
Flats (♭) are essentially the opposite of sharps: they lower a note's pitch by one semitone. For example, a flat symbol on an A note tells the player to play the note a semitone lower.
Naturals (♮) cancel the effects of a sharp or flat, returning a note to its standard pitch. For example, if a G♯ is followed by a G in the same bar, a natural is used to cancel the effects of the sharp accidental.

A key signature may consist of up to 7 sharps or flats. For example, the key signature for B major has five sharps (F♯, C♯, G♯, D♯, and A♯).

Accidentals in notation

In musical notation, accidentals are written to the left of the note and that accidental applies for the rest of the bar; canceling an accidental within that bar is done by writing in another accidental.

Below is an example of the effects of accidentals within bars:

${ \override Score.TimeSignature #'stencil = ##f \relative c' { \time 3/4 c' des d c des des } }$

Note that the natural accidental in bar 1 is used to cancel the flat accidental of the previous D♭, and in bar 2 the third note is D♭ because no accidental is being used to cancel.

Notes outside of the key signature must be indicated with accidentals. For example:

${ \override Score.TimeSignature #'stencil = ##f \relative c' { \time 4/4 \key g \major fis2 f e es } }$

Double sharps and double flats

Although not commonly seen, double sharps () and double flats () exist. They modify a note's pitch by two semitones. For example, the following passage contains an F:

${ \override Score.TimeSignature #'stencil = ##f \relative c' { \time 3/4 \key b \major fis dis e fis fisis gis } }$

Accidentals in notation

Double sharps and double flats

See also