How to Read Flat Key Signatures

When you look at a piece of sheet music, the key signature is a symbol of the key that the song is in. Key signatures are used so that sharps and flats don't have to be written for every note. Rather, the sharps and flats that are the same...

Identifying the Key

Read the flats from left to right. The key signature is next to the treble clef on a piece of sheet music. In a key signature, the flats are always presented in the same order, read from left to right: B E A D G C F.^{[2] X Research source}
1. Recall that on a music staff, there are 5 lines and 4 spaces. Each of these lines and spaces represents a white key on a piano. You can remember the notes represented by the 5 lines, from the bottom to the top, with the mnemonic "Every Good Boy Does Fine." The spaces represent notes that spell the word "FACE" when read from bottom to top. All together, the notes represented by a musical staff, in order from bottom to top, are E F G A B C D E F.
2. When you read out the notes in a scale, the flats will likely be in a different order than they are in a key signature. Just keep in mind that they're always notated in the same order in the key signature, regardless of where they occur in the scale.
Find the second-to-last flat to determine the major key. On the key signature, circle the second-to-last flat from the end. The note of that flat is the major key that the key signature represents.^{[3] X Research source}
1. For example, suppose you have a key signature with a B flat, an E flat, an A flat, a D flat, and a G flat. Since the D flat is the second-to-last flat in the key signature, it represents the key of D flat major.
2. If it's easier for you, try writing out the letters that represent the order of the flats, then circle the flats that are included in the key signature. The second-to-last letter you circled is your major key.
3. This trick only works for major keys, not for minor keys. Finding the minor key will be easier if you memorize the major keys first.
Exception: The key of F major has only one flat — B flat — so the trick won't work to identify this key. You'll simply have to memorize it.
Go down a minor third from the major key to find the minor key. Each of the 15 major keys has a corresponding (or "relative") minor key that uses the same key signature. If you know the major key, you can figure out the minor key by taking that note down 3 half steps, or 1 whole step and 1 half step. The note you land on is the name of the minor key for that key signature.^{[4] X Research source}
1. As an easy example, look at the key of C major, which has no sharps or flats. The distance from C down to B is a half step because no notes fall between them. However, the distance between B and A is a whole step. You only need to go down 1 whole step and 1 half step, which you've just done. So C major and A minor use the same key signature.
2. If you find this difficult, look at the major scale. The sixth note in the major scale is the relative minor. To continue the same example, a C major scale is C D E F G A B C. The sixth note is A, so the relative minor of C major is A minor.
Tip: Even though the major and minor scales use the same key signature, if you listen to the song, you can usually tell pretty quickly whether it's major or minor. If the song sounds bright and happy, it's likely in a major key.

Playing the Scale

Mark whole and half steps in music. If you're new to music theory and reading sheet music, you might not be familiar with whole and half steps. However, the concept is relatively simple. An interval is the distance between 2 notes. A half step is the smallest distance and occurs between 2 notes that have no other notes between them. A whole step is 2 half steps away from the original note.^{[5] X Research source}
1. Whole and half steps are easier to visualize if you think of a piano keyboard. For the white keys that have black keys between them, the black keys are half-steps and the white keys are whole steps. The space between two white keys that have a black key between them is a whole step.
Build a major scale from the key signature using the major step pattern. Start your major scale from the note that lends its name to the key. From there, play up or down following the pattern of W W H W W W H (where "W" is a whole step and "H" is a half step).^{[6] X Research source}
1. For example, the scale for the key of C-flat major is C flat, D flat, E flat, F flat, G flat, A flat, B flat, and C flat. It follows the same pattern as the C major scale, except that you start on C flat instead of on C.
2. A scale that moves from the highest note to the lowest note is a descending scale. If you move from the lowest note to the highest note, you're playing an ascending scale.
Use a different step pattern to build a minor scale. Any minor scale also involves whole and half steps. However, it uses a different pattern than major scales do. Although there are several different types of minor scales, the one most commonly used (also referred to as the "natural" minor scale) follows a step pattern of W H W W H W W.^{[7] X Research source}
1. Recall that you can find the relative minor scale by looking at the sixth note on the major scale. If you take the step pattern for a major scale and start it on the sixth note, you have the step pattern for the minor scale.
2. Since the sixth note in the C-flat major scale is A-flat, it follows that A-flat minor is the relative minor scale for C-flat major. All the notes of the scale are the same, except that you start and end with an A flat. So the scale of A-flat minor is A flat, B flat, C flat, D flat, E flat, F flat, G flat, and A flat.
Tip: The last note of the scale is not technically part of the scale — it simply brings you back to the root note. When playing the relative minor scale, you don't play that note twice.