Write Songs in Any Key with Guitar Chords You Already Know
Which guitar chords do you need to know to write songs?
If you have a capo, just 6 beginner open position chords are enough to play (and write) many songs in any key.
And if you learn just two more chord shapes (Bm and F), you’ll be able to play every major and minor chord in every key.
One of the benefits of this approach is that you can write songs in many keys without even needing to know which key you’re in. The focus is on the relationship between the chords, which are the same regardless of key.
Open Position Chords
Beginners on the guitar normally learn “open position” chords first. There’s a good chance you know these 6 major and minor chords:
These are all relatively easy to play, but this list already lets you play most of the common chords in several keys.
Below I list chords for two major keys (C major and G major) and two minor keys (A minor and E minor). The Roman numerals indicate the position of the chord in the key (with uppercase for a major chord and lowercase for a minor chord).
Notice that with just the open position chords above, we can already play most of the chords in these keys:
MAJOR
I - ii - iii - IV - V - vi
C major: C - Dm - Em - - G - Am
G major: G - Am - - C - D - Em
MINOR
i - ii° - bIII - iv - v - bVI - bVII
A minor Am - - C - Dm - Em - - G
E minor Em - - G - Am - - C - D
If you want to branch out into other keys, you don’t actually need to learn any more chord shapes. You just need a capo:
A capo is an inexpensive device that lets you play open position chords further up the neck. It’s the guitar equivalent of a transpose key function on a digital keyboard.
For example, if you put the capo on the second fret, then you can suddenly use open position chords to play most of the chords from these keys:
MAJOR
I - ii - iii - IV - V - vi
D major: D - Em - F#m - - A - Bm
A major: A - Bm - - D - E - F#m
NATURAL MINOR
i - ii° - bIII - iv - v - bVI - bVII
B minor: Bm - - D - Em - F#m - - A
F# minor: F#m - - A - Bm - - D - E
What can you do with open position chords and a capo?
With just a capo and a beginner’s understanding of the guitar, you can basically play any song that meets the following criteria:
- It contains only diatonic chords (that is, chords in a major or minor key, as listed above).
- It consists of only major and minor chords.
- It doesn’t contain both the iii and IV (or both the v and bVI for minor).
This actually covers a lot of songs.
If you can play a wide range of songs with these chords, you can also write a wide range of songs with them.
For example, you can use every chord highlighted in my in-depth post on writing major chord progressions.
Filling in those gaps
If you want to eliminate that last requirement (that you can’t use both iii and IV in the same song), you only need to learn two more chords, Bm and F. Both of these are barre chords:
F adds the missing IV to the key of C major. Bm adds the missing iii to the key of G major.
With these chords added, we can update our initial list to:
MAJOR
I - ii - iii - IV - V - vi
C major: C - Dm - Em - F - G - Am
G major: G - Am - Bm - C - D - Em
NATURAL MINOR
i - ii° - bIII - iv - v - bVI - bVII
A minor Am - - C - Dm - Em - F - G
E minor Em - - G - Am - Bm - C - D
With just those two extra chords, you can now use a capo to play all the most common chords in any key!
Note that diminished chords (like the ii° in minor) are rarely used in popular music.
How to play in any key without knowing the fretboard.
Given how much we can do with beginner chords, the chord shapes themselves aren’t really the hard part. You can get those open chord shapes down pretty fast.
As you bring in a capo to explore all of the possible keys, the hard part is knowing which chord is which.
This is part of why there’s great value in learning the fretboard.
But if you’re just trying to write music in different keys, there’s another approach that will get you writing right away. It will also deepen your understanding of songwriting.
In this approach, you focus on the relationships between the chords in a key.
Relationships between chords in any major key.
These relationships are the same no matter where you are on the fretboard.
You might have been wondering what those Roman numerals meant earlier in the post. They are a way of notating exactly the relationships I’m talking about.
The quick version is that every major key has the same kinds of chords in the same order. Using uppercase Roman numerals for major chords, and lowercase for minor, we get the following list for major keys:
I - ii - iii - IV - V - vi
I’m leaving out the diminished vii° chord, which as mentioned above is pretty rare in popular music.
If you’re interested in a deeper dive, you can read more about music theory for songwriters. But this is all we need for now.
Finding these relationships on the fretboard
We need to know the root notes of our chords in order to understand how they relate to each other. For beginner open position chords, this is pretty easy.
For these chords, the root note is the lowest note we play.
Here are all of our chords again, with the root note highlighted in orange. Notice that some of these root notes are the lowest open string played:
Remember that with these chords, we are able to play most of the chords in two major keys: C major and G major. With a capo, we’ll be able to easily transpose these to any key we want.
I’m going to call these the C-like positions and the G-like positions.
Let’s look at each of these cases in turn.
C-like positions
If we’re going to play in a major key, we want to know where each of these six chords for that key is located on the fretboard:
I - ii - iii - IV - V - vi
Since they are all in the same key, these six chords are likely to sound good together. They make a great starting point for a new song.
So let’s find them for the key of C major.
The I in the key of C major is the C major chord. We can see that this chord is rooted on the third fret of the fifth string:
The root of the I chord is also the “home” note for that key.
We can now fill in the rest of our chord numbers around it. Here I’ve marked the root of the I chord in blue to indicate it’s the home note of the whole key:
Memorizing these six notes in relation to each other will pay off many times over on the guitar.
As we’ve seen, each of these notes (and Roman numerals) is associated with a different open position chord in the key of C major:
It’s worth comparing the root notes in the last two diagrams to better understand the C major key relationships between the open position chords.
This pattern is what I’m calling the C-like positions.
When we bring a capo into the picture, we can use these same C-like positions to play in other keys.
Transposing C-like positions to the key of D major
If we place the capo on the second fret, we shift all of our chords up two half-steps. This gives us the key of D major:
I - ii - iii - IV - V - vi
D major: D - Em - F#m - G - A - Bm
Using our knowledge of the C-like positions, we can quickly identify the relationships between the chords in D major even if we don’t know the names of the chords in that key or on the fretboard.
We start by identifying our I chord. Above we looked relative to the open strings. Now we look relative to the capo:
This is the root of D major. From there, we can use the C-like positions to identify the rest of the chords in the key:
And here are the chords in D major labeled with Roman numerals:
Using C-like positions
What’s interesting is that we don’t even need to know we’re in D major to make use of this.
After all, what really matters is how a song sounds, not what key it’s in.
So as you explore writing songs, all you have to do is move the capo around and use the C-like positions to quickly identify chords that will sound good together.
Anything you learned by writing songs using only first position chords will apply to any key you try out with the capo.
G-like positions
All of these benefits apply equally to the G-like positions. So once you have the C-like positions down, you can learn these next.
Here are the chords in the key of G major:
I - ii - iii - IV - V - vi
G major: G - Am - Bm - C - D - Em
Again, we start by finding our “home” note, in this case G. This is the root of the I chord:
Now let’s fill in the rest with the G-like positions pattern:
And here are the G major open position chords with their associated Roman numerals:
Once again, it’s worth comparing the root notes in the last two diagrams to better understand the G-like positions.
Transposing the G-like positions to the key of A major
Placing the capo on the second fret moves these chords up two half-steps, and gives us the key of A major:
I - ii - iii - IV - V - vi
A major: A - Bm - C#m - D - E - F#m
Here are the G-like positions relative to the capo on the second fret:
And here are the chords in the key of A major with their Roman numerals:
We can use these G-like positions just like the C-like positions, moving the capo and the positions wherever we want.
And once again, we don’t actually need to know which chords we’re playing to quickly find chords that work together.
Identifying your chords after the fact
When you’re writing a song, it doesn’t really matter what key you’re in. The most important thing is finding combinations of chords and melodies that sound good.
But once you’ve written a song using the method above, it’s pretty easy to figure out which chords you were playing.
Let’s say you wrote your chord progression down using Roman numerals (which you can do without actually knowing the key if you know the C-like and G-like position patterns).
To determine which key you’re in, look up the I chord root note on a chart of all the notes on the fifth and sixth strings:
If it’s an A, then you’re in the key of A major, for example.
You can then use the following chart to look up the rest of the chords relative to that key:
I - ii - iii - IV - V - vi ------------------------------- C - Dm - Em - F - G - Am Db - Ebm - Fm - Gb - Ab - Bbm D - Em - F#m - G - A - Bm Eb - Fm - Gm - Ab - Bb - Cm E - F#m - G#m - A - B - C#m F - Gm - Am - Bb - C - Dm Gb - Abm - Bbm - Cb - Db - Ebm G - Am - Bm - C - D - Em Ab - Bbm - Cm - Db - Eb - Fm A - Bm - C#m - D - E - F#m Bb - Cm - Dm - Eb - F - Gm B - C#m - D#m - E - F# - G#m
What’s interesting about thinking in terms of Roman numerals is that you can also easily transpose your song to other keys by moving the capo around. This can be useful to accommodate a higher or lower vocal range, for example.
Some limitations of this method
If you’re writing (or playing) popular music, you can get pretty far with just major and minor chords. But eventually you’ll probably want to add greater variety, such as 7th chords, 6th chords, suspended chords, and so on.
Of course, this means you’ll need to know more than 8 chord shapes! But it’s worth keeping in mind that if you learn the open position versions of these chords, you’ll be able to easily adapt them to the system we’ve explored in this post.
To give one quick example, the open position D7 shape played with the capo on the second fret gives us the E7 chord:
So if you’re playing in A major with G-like positions, you can easily throw in an E7.
It doesn’t need to be all or nothing. If you find that this system works for you, then you can gradually learn more chords to add to your vocabulary. This might happen naturally as you learn other people’s songs, for example.
We’ve only scratched the surface, ignoring chord voicings, inversions, and other more advanced topics. These are all worth exploring, but for now you have a system that can quickly get you writing songs in any key!