Key Signature

Yet another area of theory that often proves a bit confusing. You may have already had a go at key signatures. Your music teacher might have explained (multiple times) something called the circle of fifths to you. You may have even tried to simply remember the many combinations of sharps or flats and which key they represent.

There's a much easier way. In a few minutes you will be able to work out any key signature, no matter how many sharps or flats. It's easy and you don't need to know anything about the circle of fifths.

Just as a side note, it is eventually well worth understanding the circle of fifths as it relates to much more than key signatures, but for key signatures alone, there is a much MUCH easier method.

Last thing - this method is for working out major keys. We'll deal with minor keys later.


Look at this key signature:

Pasted Graphic

To work out the key signature all you do is look at the last sharp on the right. It's G-Sharp.

Now go up one semitone from G-Sharp. Where are you? "A". So, it's A-Major. Simple as that!

It works with any of combination of sharps. Try this one:

Pasted Graphic 1

The last sharp on the right is A-Sharp. One semitone higher than A-Sharp is "B". It's B-Major. Try it yourself on any key signature with sharps - it's a really easy method.


Flats are slightly different but just as easy. There is one exception which is the key signature with only one flat:

Pasted Graphic 2

You just have to remember that this one is F-Major.

Now any key signature that has more than one flat is easy. Take a look at this one:

Pasted Graphic 3

All you do is look at the last but one flat. In this case, it's E-Flat. The key is E-Flat major. You don't need to go up a semitone like you do with sharps.
Look at this one now:

Pasted Graphic 4

Ordinarily a key signature like this might scare you. But look - the last but one flat (the second from the right) is G-Flat. So it's G-Flat major.

It really is that simple!

About Minor Key Signatures

Remember, every key signature represents a major and a related minor key. It could be either - it depends on the actual music which one it actually is. The quickest way to work out a minor key signature is first work out the major key, then move down three semitones.

An example - what is this minor key?

Pasted Graphic 5

Work out the major using the method above. It's E-Major. Now, to work out the the minor key, go down three semitones from E. You get to C-Sharp. So it's C-Sharp Minor.

I hope that' made key signatures a lot easier for you. If you'd like any further clarification, contact me.