Accidentals in music rules

Accidental, in music, sign placed immediately to the left of (or above) a note to show that the note must be changed in pitch. A sharp (♯) raises a note by a semitone; a flat (♭) lowers it by a semitone; a natural (♮) restores it to the original pitch.

1. How long does an accidental last in music?
2. How are accidentals used in music?
3. What are the 5 accidentals in music?
4. Does an accidental apply to the whole bar?

How long does an accidental last in music?

Accidentals last only until the end of the measure in which they appear. In the example below, note C sharp (in bar 1) is cancelled by the bar line.

How are accidentals used in music?

A music accidental can turn a pitch sharp, flat, or back to its natural state. The most commonly used accidentals in music are the sharp (♯), the flat (♭), and the natural (♮). These accidentals raise or lower a pitch by a half-step, making the pitch either higher or lower than it was before the accidental.

What are the 5 accidentals in music?

The most common accidentals. From left to right: flat, natural, and sharp.
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Standard use of accidentals

• 1: G♮, G♯, G♯ (the sharp carries over)
• 2: G♮ (with courtesy accidental), G♭, G♭ (the flat carries over)
• 3: G♭ (which is tied from the previous note), G♯, G♮ (the natural sign cancels the sharp sign)

Does an accidental apply to the whole bar?

The accidental will apply to following notes in the same measure / bar but not after that. If it is needed to cancel the effect before then another accidental (maybe a natural sign) will be required. Oddly, although a sharp or flat in the key signature affects the same note in other octaves, an accidental does not.