Everything You Need to Know About Accidentals in Music
Accidentals in Music: ♮♭ ♯
Hello musicians, in this lesson we are going to go over a basic yet important topic - Accidentals!
Accidentals are used all the time in written music, in fact, there is no written music without accidentals.
This topic itself is fairly simple but it does have a few important rules you need to follow and a few useful techniques you need to know in order to make everything as simple as possible right from the get-go.
What are accidentals?
In music, an accidental is a symbol that signals a modification of a pitch.
A musical accidental can sharpen a pitch (raise it up), flatten a certain pitch (lower it down), or keep it right at its place (natural).
The sharp (#) and the flat (b) symbols will raise or lower a note by a half step, making it higher or lower than its former state.
The difference between sharp and flat is that a sharp will always raise and a pitch and a flat will always lower a pitch.
Why are they called accidentals?
The word Accidental comes from old Latin, the specific term that was used for hundreds of years was accidere which means befall or occur, its meaning was more of a certain change in the current state.
Today we use the word accident a little differently, we use it to define something that is chance related and usually bad.
When to use accidentals
We use accidentals in 3 main cases:
To define a scale - one or a set of accidentals will appear next to the clef, the combination accidentals indicate the scale of a certain piece. When using this method, a composer won’t need to write accidentals on each note of the piece as it is indicated at the beginning.
To raise or lower a certain note outside a certain key - for example, a musical piece written in C major doesn’t have any sharp or flat notes in it. If a composer wants to add an F# to the piece, it will be written next to the F note, therefore, raising it to F# (F sharp).
When writing chords (not in notation) - This is the most common way everyone uses accidentals (even if you are not an educated musician). For example, the chords Ab7 or F#maj7.

How many accidentals are there in music?
The total of accidentals used in music is 3:
Sharp, which raises a pitch, gets the ♯ symbol.
Flat, which lowers a pitch gets the♭ symbol.
And Natural which sets a note in its natural place gets the♮ symbol.
The flat and sharp symbols can be doubled, creating a double sharp (𝄪) and a double flat (𝄫).
The use of flat and sharp Accidentals
How long does a sharp or a flat last?
There are 2 answers to that question:
-
If a sharp or a flat is indicated in the key signature, it will last for the whole musical piece (unless there is a change in key along the piece).
- If a flat or a sharp note is not in the key signature, it will last a whole measure (a measure is a bar) and then will get back to its key state.
The Double Sharp in music
A double sharp is an accidental that contains 2 sharps in it, meaning that the note equipped with this accidental will be raised by two semitones (or half steps).
The symbol for double sharp will be “x” (the actual symbol is 𝄪, but it’s rather small in the computer keyboard configuration).
For example, the note F# (F sharp) is the black key between F and G (6th string, fret 2 on the guitar) and the note Fx (double sharp) is the G key on the piano (6th string, 3rd fret on the guitar).
The Double Flat in music
A double flat is an accidental that contains 2 flats in it, meaning that the note equipped with this accidental will be lowered by two semitones.
The symbol for a double flat is “bb” (the actual symbol is 𝄫, but again, it’s rather small in the computer keyboard configuration).
The difference between a sharp and a double is that a sharp raises the note by a half step and a double raises the note by 2 half steps.
Another example, the note Ab (A flat) is the black key between F and G (6th string, fret 2 on the guitar) and the note Fx (double sharp) is the G key on the piano (6th string, 3rd fret on the guitar).
Why do we use a double sharp or double flat in music?
The reason double sharp and flat are used in music lies in notation, in notation you can indicate two factors while writing a note - the note itself and its pitch.
For example, a note can be F but its pitch can vary between F double flat to F double sharp. Composers will “stay within the borders” of a certain scale, it is just the rules of notation.
☝🏽 Remember, scales are patterns of steps, not specific pitches.
In Practice:
In practice, you will never see a double sharp or flat in a key signature, maybe if there was a scale after C# major… ah.. nevermind... not interesting! We want practical stuff! OK.
The double sharp is mainly used for adhering to the rules of music theory but you will definitely come across double sharp in a few occasions such as:
-
Preventing multiple jumps from sharp to natural on the same note - for example, in a piece of music written in F# major in which the composer wants to use the D note (there is D# in the F# major scale). Instead of jumping between D# and D natural, the composer may just use C double sharp.
- Properly writing chords - as (we hope) you already know, the format of simple chord building is 1-3-5 (root, 3rd, 5th) therefore when building an A chord we will use A-C#-E notes (and NOT A-Db-E), that means that the proper writing for A# is A#-Cx-E#.
❌ Canceling a double sharp or flat - The same cancelation rules of the flat and sharp accidentals apply to the doubled ones. They will automatically get canceled after the end of a measure.
If you want to cancel a doubled accidental in the same bar it appears, you need to add a sharp, a flat, or a natural accidental to the note you want to be reversed.
Is there a triple sharp or a triple flat in music?
The simple answer is no, but there is some confusion around that term because the A major scale contains 3 sharp notes (F#, C#, G#), or one might say triple sharp notes.
The same goes for Eb major scale which contains 3 flat notes (Bb Eb Ab), or a triple flat... BUT DON’T USE THAT TERM, no one uses it!
You will probably never use 3 sharp accidentals altogether on one note, but there are actually triple flat and sharp, the triple flat is a backward flat symbol and the triple sharp has an added vertical line.
☝🏽 These forms are very rare and will usually be indicated also in some kind of remark from the composer on the sheet music.
Why is there no B or E sharp in music?
Well, of course, there is a B# and an E# in music! These 2 notes are also totally different from each other, the only place that they are the same is on the keyboard or the frets of a guitar.
In theory, we can see that there is actually a B and E sharp in music, for example, the notes in F# major scale are F#, G#, A#, B, C#, D#, E#.
The same goes for C or F flat...
There is a C flat scale as well as an F flat scale. For example, the scale Cb major contains both C flat and F flat notes.
Where does it all come from? 🧐
Let us explain, up until the middle of the 19th century, the tuning of instruments was done according to a different older tuning system called “just tuning” and in these tuning setups an E# and an F note, for example, were actually different in pitch.
The transitional period that came around the mid-19th century was accompanied by a new tuning system (the one we use today) in which E# and F are in the same pitch.
The Natural ♮
The natural accidental is a little different, rather than raising or lowering a pitch, it locks it in its place.
For example, in a musical piece written in G major scale we have an F#, if a composer wants to use an F note, he will add the natural accidental to the note.
How long does a natural accidental last?
The same rules that apply to the sharp and flat accidentals apply for the natural one. It will last only for a whole bar (or a measure).
I sometimes see a useless natural, sharp or flat accidental, what does it mean?
There is a type of natural called a Courtesy Accidental, the purpose of these accidentals is to clear any doubt the reader might have about the correct pitch of a certain note.
It will come after some change that was done previously to make sure the reader knows to return to the pitch indicated in the key signature.
It is useful especially in sight-reading when everything works in real-time and it is called a Courtesy Accidental because it doesn’t have to be written, as stated before, an accidental gets canceled at the end of the bar it appears in.
Why are brackets put around some accidentals?
The accidentals appearing in brackets are Courtesy Accidentals as well!
Courtesy Accidentals will sometimes appear with brackets and sometimes without. The brackets are there to make things even clearer and will be put in brackets to prevent even a tiny chance of confusion.
The accidentals in brackets will usually indicate an obvious or common mistake that the reader should avoid.
☝🏽 Courtesy Accidentals are Accidentals that you can emit and the musical piece will stay the same (it might be a little harder to read but the notes will stay in their place).
Accidentals in Scales:
Accidentals (flats or sharps) define the key signature, depending on the number of flats OR sharps displayed at the beginning of a musical piece.
The accidentals are written at the beginning of a musical piece and mark all the sharp or flat notes for this piece. This way the composer won’t have to add countless accidentals if a piece is written in a key with flat or sharp notes.
How to write the scales Accidentals?
The accidentals are written at the beginning of a musical piece, next to the clef. There is a specific order in which the accidentals are arranged:
The Accidentals in keys that contain sharp notes will be arranged in ascending Perfect 5th intervals (or descending 4th intervals).
The Accidentals in keys that contain flat notes will be arranged in ascending Perfect 4th intervals (or descending 5th intervals).
How do you know what sharps or flats are in a scale?
There is a fairly simple system to memorize the Accidentals of each key. As stated before, the order of which the Accidentals that define keys are arranged is always the same - Perfect 4th or 5th intervals.
Let’s take a look at the following set of sharps and flats
Notice any similarities?
These are the same arrangements in different directions.
The flat notes order - Bb, Eb, Ab, Db, Gb, Cb, Fb
☝🏽 In order for this method to work you need to memorize this sequence from start to end and backward.
Now, how to recognize a key instantly…
Let’s look at the sharp note sequence first. When trying to figure out what key you are looking at and the key signature contains sharp notes, the key will always be half step above the last sharp note.
For example, if we try to recognize a key with F#, C#, G#, we need to move one half-step above the G# (which is the last sharp). The goal note is A, therefore the key that contains these 3 sharp notes is A major.
Note: the last sharp is B# and to prevent any confusion, the scale it indicates is C#.
When trying to recognize the key signature with flats next to the clef, we will always look at the flat before the last flat.
For example, when we see Bb, Eb, Ab, and Db next to the clef, which is the one before the last?
Ab is one before the last, that means that this is Ab major scale!