When you’re first learning your musical key signatures, it can feel a little overwhelming. With twelve major keys and twelve minor keys, the sharps and flats pile up fast, and it can be easy to get them all mixed up. While you could hit the flashcards and memorize each key signature one at a time, we’re going to save you some time by giving you the best key signature hacks!

Before we dive in, let’s take a look at all of the key signatures you’ll need to memorize. Remember that each key signature has both a major and minor key. The key signatures that share the same key signature are known as relative keys.

C Major and A Minor

Though we’re about to show you some useful tricks, the first thing you need to know when memorizing your key signatures is that there is no trick for C Major or A Minor. Both C Major and A Minor have no accidentals in their key signature, so you’ll have to memorize these without any hints! The key signature for these keys looks like this:

Major Sharp Keys

When you’re approached with a sharp (♯) key in your sheet music, you can determine the corresponding major key by observing the last sharp (or the sharp furthest to the right) in the key signature. Look at the example below and see the sharp highlighted in green.

To determine the major key, all you have to do it go one half-step up from the last sharp listed.

  • In this example, an A-Sharp is highlighted.
  • One half-step up from A-Sharp is B.
  • The key is B Major.

Another way to think of this method is to think of the last sharp listed as the leading tone of the major key. In B Major, the leading tone (or 7th scale degree) is A-Sharp.

Now that you know the hack, you can easily use this trick on any other key containing sharps.

Major Flat Keys

If you thought that was easy, our trick for memorizing your major flat keys (♭) is even easier! With flat key signatures, all you have to do is look to the second flat from the right to determine the major key.

In the example above, notice that a D-Flat is highlighted in green. And just like that, D Flat Major is the key! No additional steps required!

We have to admit, there is one catch with this trick. Since the key of F Major only has one flat, it’s impossible to locate the second flat from the right in that key signature. So just like you’ll have to wire C Major and A Minor into your brain with no extra help, you’ll have to do the same for F Major.

F Major only has one flat: B-flat.

Minor Keys

The true key to memorizing your minor keys is memorizing your major keys first! Once you know which major key signature you’re in, you can find it’s relative minor key in seconds!

To determine the minor key, simply go down a minor third from the major key.

You can think of a minor third as 1.5 steps, three half steps, or one whole-step and one half-step. Choose the method that makes the most sense to you!

Now, let’s put this trick into practice! Say you are given the key signature below:

We can determine by using the trick we learned earlier that one half-step up from F Sharp is G, therefore we are in G Major. Now, to find the relative minor key, find the note a minor third below G.

Looking at the image above, you can determine that the relative minor key for G Major is E Minor. 

If this method is a little too confusing, you can also find the relative minor by determining the sixth scale degree in the major key. E is the sixth note (or scale degree) in the G Major scale.


Now that you know the secrets, you’re well on your way to becoming a key signature expert! All that’s left is to practice them!

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