Chord progressions

A “chord progression” simply means: a series of chords. Most tunes are harmonized with three or more chords, and
the order of those chords is called the chord progression.

A verse or chorus of a song often starts out on the home chord (the I chord in the key), then moves through a series
of other chords and finally ends up on the home chord again.

Many songs (as well as classical pieces) use the same sequences of chords, and in this article we’ll look at some of
the most common ones.

A very basic progression is I – IV – V. If we’re playing in the key of C that would be C – F – G. After the V chord
you would typically play the I chord again.

Often the IV chord in this sequence is replaced by the ii chord. That is a minor chord. The progression then becomes
I – ii – V, or C – Dm – G in the key of C.

Again, this progression leads us back to the home chord, so the next chord after ii – V is most likely to be the I
chord. This progression is therefore known as ii – V – I (or 2-5-1).

Remember that the V chord is often played as V7. That is how you can recognize this progression. If you see a
minor chord followed by a dominant-7 chord, followed by a major chord: it’s a ii-V-I.

An extension of this progression is the 1-6-2-5 pattern. (For some reason this progression is often written using
normal numbers instead of Roman numerals.)

In the key of C, it goes like this: C – Am – Dm – G7

One of the names these chords go by is the “Blue Moon progression”, but there is a huge number of other songs that
use it too.

Go play it on the piano and then hum the verse of “Blue Moon” or “Heart and Soul”. Don’t tell me it doesn’t sound
familiar.

It is really easy to compose your own tunes on top of these four chords, because it will make almost any melody
sound good, but we’ll get into that in a later article.

If you already know about the Circle of Fifths, notice that these chord progressions, 2-5-1 and 1-6-2-5 (or rather 6-2-
5-1), are simply trips around the circle. Movement in fifths gives the strongest type of sound that our ears like, so it
is no wonder that these patterns are used so much.

Because Dm can substitute for F (see above), you can also play 1-6-2-5 as 1-6-4-5, and vice versa. It’s only a small
variation in the sound.

What I want you to do now is go through your stack of sheet music or leadsheets (if you have them) and see if you
can find these chord progressions in those songs. Even classical pieces will have them.

You can also find the chord sheets of many tunes online. Just go to Google and type in:

name of the song chords tabs

For example:

blue moon chords tabs

The words “chords” and “tabs” will tell Google to look for websites that have chord sheets. You might have to dig
around for a while but usually you can find a chord sheet for most music.

Remember that you can spot a ii-V-I by looking at the type of chords: a minor chord followed by a dominant-7
chord, followed by a major chord. This is important, because sometimes — especially in Jazz tunes — you may find
a ii-V-I that uses chords that are not in the key of the song.

For example: C Am F G7 Gm C7 F …

The first four chords are in the key of C, but Gm isn’t and neither is C7. What you see here is a ii-V-I, namely Gm-
C7-F, that is used to modulate to another key. The F is now the new I chord. At some point the chords will modulate
back to the original key, likely using another ii-V-I. That’s a typical thing for Jazz tunes.

So much for the theory. It’s good to learn these chord patterns (1-6-2-5 and 2-5-1) in every key, so go to your piano
and play around with them.

Chord progression maps

Speaking of chord progressions, there is a very cool web site called chordmaps.com where you can learn all about
them.

For example, here is a chord progression map for the key of C.

In the key of C, the C chord is the home chord, the most important chord. This is where chord progressions begin
and end.

Here is how to read the chord progression map: from the C chord you can go to any of the other chords, and then
you have to follow the map back to the C chord.

So you could start at C and jump all the way up to the A chord (top-left). From A you go down to Dm, then to G to
Em to Am to F to G and finally back to C.

But that is only one possibility. We could also have gone from A to the shorter route of Dm to Em to F to C.

The possibilities aren’t endless, though. If that were true, we wouldn’t need the map. The map exists because not all
chord progressions sound good.

The site also has maps for all other keys and a generic map that works with Roman numerals.

Play around with it! It’s a wonderful tool for learning the rules of harmony.

How to find the key of a song (by ear)

If you know the “key” of a song, you’ll know which notes the melody uses, and which chords to play. Finding the
key of a song is the first step of transcribing.
Playing from sheet music, you can find the key by looking at the key signature. But if you’re playing by ear, you’ll
have to do some experimentation.

First, I play along with the song and try to find the scale that matches the melody.

There is a wonderful program called Transcribe! that can help you with this. It can loop endlessly through sections
of the song and even slow the music down while keeping it at the same pitch. Very handy!

Most songs are in a major key and there are 12 possible major scales. If you know these scales by heart it shouldn’t
be too much of a problem to find the right one.

For example, if I press the A on the piano and it sounds wrong with the music, then I can exclude all the scales that
have the A tone. I know the song will be in one of the following keys: Eb, Ab, Db, F#, or B.

Now I can restrict my search to the tones of these five scales. Usually after trying a few tones you’ve found the right
scale.

I already mentioned in a previous article that the same scale is used for a major key and its relative minor key. For
most songs you can assume they are in a major key, but some songs are in a minor key. If you’re not sure, you’ll
have to look at the chords for additional clues.

Usually the very last chord of the song — and often also the very first chord of the song — will be the home chord,
or the I chord. That is, the chord that names the key. If a song ends with the E chord, then chances are it is in the key
of E.

You can verify this by playing the E chord along with the song — most of the time it should sound good. In the
spots where it doesn’t sound good, you’re supposed to use another chord from the key of E. (Typically the V7 chord,
in this case B7. Or the IV chord, in this case A.)

If you found the E major scale works for (most of) the song but E chord sounds wrong somehow, then try C#m,
which is the relative minor of E. If C#m works, then the song is in a minor key.

In a similar vein, you can listen for the final tone of the song. Just like the final chord tends to be the chord that
names the key, so is the final tone. Of course, there are exceptions but 95% of the time this will be true.

Here is another tip that I found on the internet some time ago:

1. Sing along with the song for one or two lines while it’s playing, and then:
2. Sing DO-RE-MI-FA-SOL-FA-MI-RE-DO.
3. The final “DO” you land on is the key you are trying to find.

It’s not an exact science, but it works.

How to find the chords for a melody

If you know the melody to a tune, then how do you find the chords to accompany that melody?

My best advice: join Piano Magic

(Really, I mean it!)

In the mean time, here’s a quick summary of how to harmonize melodies:

1. Find out what key the melody is in

2. Learn the I, IV and V7 chords of that key. In the key of C these would be C, F and G7.
3. Press the I chord and play the first notes of the melody.
4. When the melody and the chord no longer seem to fit together, switch to one of the other two chords. This
usually happens at the beginning of a new measure.
5. Repeat until you reach the end of the song. Usually the song will end on the I chord.

If the I, IV or V7 chords match but aren’t completely satisfactory, then try the minor chords from the key (vi, ii, or
iii). In the key of C these would be Am, Dm or Em.

If the I, IV or V7 chords don’t match at all, then try an accidental chord such as II7 or III7. In the key of C these
would be D7 or E7.

In case you didn’t notice yet, there is a close relationship between the melody and the current chord: melody tones
are chord tones.

That means the tones that make up the melody are the same tones that make up the chord. Consequently, if the
melody switches to the tones from another chord, it is time to change chords.

For example, if you’re currently playing C chord, then the melody will focus on the tones C, E and G. The melody
may still include other tones, but they will be quick passing tones.

If the melody lingers on a tone that is not in any of the chords from the key, you should find another chord that does
have this tone.

For example, if you encounter an long F# tone in the key of C, then a likely candidate for the chord is D7 (which is:
D-F#-A-C) but it could also be B7 (which is B-D#-F#-A).

That’s about it.

Relative major and relative minor

This is the major scale of C: C D E F G A B C

This is the natural minor scale of A: A B C D E F G A

Notice anything? That’s right, they both use the same tones!

When the tones in a piece come primarily from the C major scale, we say that the piece is “in the key of C major” or
just “in the key of C”.

When the tones in a piece come form the A natural minor scale, we say that the piece is “in the key of A minor”.

Since both of these scales contain the same tones, the key signature of both the C major key and the A minor key
are identical: white keys only, no sharps or flats.

Because of this, the key of A minor is called the relative minor of C major.
Conversely, C major is called the relative major of A minor.

Finding the relative key

Here are the rules:

 The 6th tone from a major scale names its relative minor.
 The 3rd tone from a minor scale names its relative major.

The 6th tone from the C major scale is A, so A minor is the relative minor of C. The 3rd tone from the A natural
minor scale is C, so C major is the relative major of A minor.

If you’ve read the article on inverting intervals, this should make sense to you because: 9 – 6 = 3 and 9 – 3 = 6.

You can also count it out in half-steps:

 To go from major to relative minor, go three half-steps down.

 To go from minor to relative major, go three half-steps up.

What is the right name?

From the key signature alone it is impossible to find out which key — major or minor — you’re really in. You’ll
also have to look at the melody tones and at the chords.

Pay attention to the following:

 The name of the piece. If it’s called “Sonatina in C major”, it’s probably in C major.
 If the piece begins or ends with a major chord, it is most likely in a major key.
 If the piece begins or ends with a minor chord, it is most likely in a minor key.
 Most of the time, the melody tone the piece ends on names the key. So if the choice is between the keys of C major
and A minor and the piece ends on a C tone, then the answer is C major.
 If the melody contains accidentals (sharps and flats that are not in the key signature) then you could be in a minor
key. The harmonic and melodic minor scales may be used for the melody and chords, and they contain sharpened
tones.

Note: often a piece begins in minor but ends in major. Somewhere along the way it “modulates” from the minor key
to the relative major key. It starts out sad but ends happy.

Songs that begin in major will often switch to a minor key on the bridge (this may be the relative minor, but it could
also be another minor key) and then modulate back to major for a new verse or the chorus.

Key signatures
The “key” of a piece determines what tones can be used by the melody and which chords will harmonize the
melody.

There are 12 major keys and 12 related minor keys.

The notes that can be used are given in the key signature. In written music, you can find the key signature on the
left of each line.
The key signature consists of one or more sharps or flats, or none at all. For example, if you see the following bit of
music:

This means the scale for this piece has two flat tones (black keys) and five regular tones (white keys). Specifically, B
should be played as Bb and E should be played as Eb. This is either the key of Bb major or G minor.

Likewise for a key signature with sharps:

Now we have three sharpened tones — F#, C# and G# — making this either the key of A major or F# minor.

Note: The key signature is not only important for written music. If you play by ear, you’ll still have to work with
keys and so you’ll still have to know which notes are sharps and which are flats.

Here is a handy table that lists all major and minor keys with their scales and key signatures:

Major key Minor key Signature Scale tones

C A min CDEFGAB

F D min F G A Bb C D E

Bb G min Bb C D Eb F G A

Eb C min Eb F G Ab Bb C D

Ab F min Ab Bb C Db Eb F G

Db Bb min Db Eb F Gb Ab Bb C
Gb Eb min Gb Ab Bb Cb Db Eb F

Cb Ab min Cb Db Eb Fb Gb Ab Bb

C# A# min C# D# E# F# G# A# B#

F# D# min F# G# A# B C# D# E#

B G# min B C# D# E F# G# A#

E C# min E F# G# A B C# D#

A F# min A B C# D E F# G#

D B min D E F# G A B C#

G E min G A B C D E F#

Of course, melody and chords will from time to time use tones that are not in the key signature. Such tones are called
“accidentals”. More about them later.