Playing the guitar in key – or any other instrument for that matter – means that we’re playing the notes that match the tonality and pitch of the backing track or the accompanying instruments. In other words, it means we’re playing the instrument in a way that actually sounds good with the other instruments, backing track, etc.
And there are a few ways of discovering the key of a song on guitar but of course, I prefer how I do it the most because it’s what worked for me. That said, everyone has their own way of going about things. The most common, however, is what I’ve listed here:
To find the key of any song on guitar
1) Identify the root and last note of the song
2) Play every note from the root note in the order of the major diatonic scale to match the scale
3) Repeat the process until you’ve found the scale.
The method I just listed works for a lot of people but I prefer to use the modal shape patterns to inform me of what key it’s in, because, at least if you know the modes, it’s much easier. I also find it’s more reliable and with less guesswork. We’ll explore how that works in detail in this article.
Finding the Key of Any Song On Guitar
1) Memorize the following scale shapes: Ionian, Dorian, Phyrgian, Lydian, Mixolydian, Aeolian, and Locrian.
2) Listen to the other instruments or the backing track/song
3) Find one note on the guitar that sounds like it goes with or matches the other instrument.
4) Using the first note from above, find the following 4-5 notes that match the song/accompanying instrument.
5) Once you’ve figured out the first 4-6 notes of the song that sound good with the other instruments, match those notes to one of the aforementioned scale shapes from step 1.
At this point, you should have 6-7 notes that go with the song, and you should have outlined the basic scale/mode shape that matches the track.
6) Determine what key the song is in through the use of the Mode Shape, in relation to its foundational Key Signature.
There are a number of different ways to figure out the key signature of a song, however, I’m going to show you how I go about doing it.
For the sake of giving you what you want right away, I just laid out the basic step-by-step process for figuring out the song’s key, and now, we’ll explore in detail what all of the steps mean.
For a long time, I struggled to figure out the key signature of even the most basic song, with the exception of when I had access to the music or the standard notation.
However, it all changed once I figured out 7 different scale shapes: the Ionian, Dorian, Phyrgian, Lydian, Mixolydian, Aeolian, and Locrian modes.
The method that I use to figure out the Key Signature of a song is quite a bit different from most others you’ll hear out there, however, I’ve found that this method works amazingly for me, and has changed my guitar playing for the better.
For this tutorial, I’m going to assume that you are at least familiar with all the key signatures. There are a number of ways to memorize them, and thankfully, it’s not an insurmountable task. I’ll explore it in another article some other time.
1) Memorize the Mode Shapes of the C Major Scale
For this, you have to memorize the aforementioned modes that I laid out above. Again, these are the modes:
The modes are terms that are used to describe the musical context in which notes are played.
A lot of people on the internet like to say that a mode is just the notes of a particular scale, but starting at a different point, and while that’s true in a way, it’s not entirely the whole story.
With that said, this tutorial isn’t about the modes, so we’ll discuss that another day.
For the sake of this tutorial, we’re going to think of the modes in that way, however, because it’s useful in the context of this article.
For example, understanding that the Dorian Mode is when you start playing the notes from the second degree of the scale gives you a scale shape for figuring out the notes of the accompanying music.
It’s useful to memorize it this way, especially in the context of learning how to improvise, and you’ll understand why after you’ve read this entire article.
I’ll show you what I mean right now using the notes of the C Major Scale.
Ionian – Starting on the first degree of the Scale.
C, D, E, F, G, A, B, C,
The Ionian mode means that you’re starting the notes from the C.
Dorian – Starting from the second degree of the scale.
D, E, F, G, A, B, C, D
Phyrgian – Starting from the third degree of the scale
E, F, G, A, B, C, D, E
Lydian – Starting from the fourth degree of the scale
F, A, B, C, D, E, F
Mixolydian – Starting from the fifth degree of the scale
G, A, B, C, D, E, F, G
Aeolian – Starting from the sixth degree of the scale
A, B, C, D, E, F, G, A
Locrian – Starting from the seventh degree of the scale
B, C, D, E, F, G, A, B
So why does all of this matter?
It matters because if you memorize the notes of the C Major scale starting from each position of the scale, you essentially have at your disposal seven different shapes that allow you to easily figure out the key signature of a song.
When you’ve memorized what all of the key signatures are, and you know how the seven different mode shapes look, what you’re able to do is apply those movable shapes all over the guitar’s neck, that way you can figure out the key of the song.
So here are what the modes of the C Major Scale look like on the guitar:
***It’s worth noting that the mode shapes I’ve laid out below don’t have to end on the same note that they start on. The purpose of memorizing them in the way that I’ve laid out below is to allow you to figure out the key of the song.
However, if you wanted each mode shape to actually sound like the mode, you want to end the scale on the same note as it starts on, for instance, starting on the 8th fret of the E-string, C, and then up to the 13th fret of the B-string C.
Ionian (Scale starting on root note): This is basically what the regular scale looks like in the regular root position. In other words, it’s the same as just the regular Major Scale.
Dorian (Starting on the second note D):
Phyrgian (Starting on third note E):
Lydian (Starting on the fourth note F):
Mixolydian (Starting on the fifth note G):
Aeolian (Starting on the sixth note A):
Locrian (Starting on the seventh note B):
Memorize these scale shapes by playing them each once a day for about a week, or perhaps even two.
That should be enough to solidify them in your brain, and then be able to move them across the neck to go with each key signature.
Remember, the idea behind memorizing these scale shapes is not to actually create the modal sound, but instead, to be able to play the Major Scale (more on scales in my article) starting from 7 different notes.
2) Find one note on the guitar that sounds like it goes with or matches the other instrument.
Now that you’ve memorized the mode shapes of the C Major scale, all you have to do is find ONE note that matches the other instruments or the song.
3) Using the first note from above, find the following 4-5 notes that match the song/accompanying instrument.
And then play another 3-4 notes that fit the song, and you should begin to recognize what mode shape is being utilized.
For instance, if the song is in the Key of C Major, and you play the 18th, 17th, and 15th fret on the B-string, you have three notes of the F Lydian mode shape.
Then, if you play the 15th, 17th, and 19th fret on the high E-string, and it sounds like it goes with the song, that means that you just outlined the top six notes of the F Lydian mode shape.
4) At this point, you should have 6-7 notes that go with the song, and you should have outlined the basic scale/mode shape that matches the track.
For instance, if you’ve played the 15th fret G, and the 17th fret A, as well as the 19th fret B, you have the final three notes of the F Lydian shape.
If you memorized the Lydian shape, you know the order of notes that will follow.
F Lydian will look like these notes below:
5) Determine what key the song is in through the use of the Mode Shape, in relation to its foundational Key Signature.
OK, so here is where it all comes together.
Because you discovered that the D Lydian shape works with the song that you’re playing over, and you know that the Lydian shape starts from the 4th note of a major scale, that means that we can easily discover the foundational key signature on which that mode is based.
You have F Lydian, which means E must be the Phyrgian mode shape, D must be the Dorian shape, and finally, C is the Ionian shape, or the Major scale shape.
The Key of C Major has no sharps or flats, which means that the E Phyrgian mode will sound good, the D Dorian mode will sound good, and the C Ionian mode (C Major) will sound good with the backing track or the other musicians you’re playing with.
Now you know what key you’re in. You’re in the Key of C Major.
And then Voila! You just figured out the key of the song.
Truthfully, this seems complicated but it really isn’t. All you have to do is memorize the order of notes in each mode shape, and then you can easily apply those all over the neck to figure out what notes will sound good with the rest of the music.
Amazingly, this has the added benefit of giving you seven different shapes to play whenever you’ve figured out the song’s key signature.
Additionally, you can take this idea even further by learning arpeggios of each degree of the scale, and then you have an additional seven different arpeggios that you can use to play whenever you figure out a song’s key.
Truthfully, some notes, chords, and arpeggios will sound better than others, depending on the notes of the music that you’re playing along too, but the point is that you now have at your disposal a ton of different shapes and arpeggios that you can use to jam over any backing track.
I highly recommend checking out the accompanying YouTube video that’s shown below, because I go through and show you exactly what I mean, as well as show you a bunch of different songs that you can jam over easily.
Unfortunately, I can’t use copyrighted music, so I had to use some of my own, but the idea is still illustrated just fine.
Let’s quickly do another example that way you have a better idea of what was just done here.
Let’s say that you’re listening to a song, a backing track, or you’re playing with other musicians and they don’t know what key you’re in.
If you start jamming on the 11th fret Eb, and it sounds good, and then you play the 13th fret F, and then the 15th fret G, you already have a pretty good idea of what modal shape this is.
It can be either the Ionian shape, the Mixolydian Shape, or the Lydian shape because they all start in the same way: two notes apart from each other.
If you then play the 11th fret ‘Ab’ on the A-string, then the 13th fret ‘Bb’ on the A-string, and then the 15th fret ‘C’ on the A-string, you just outlined the first six notes of the scale.
From there, if you find that the 12th fret ‘D,’ the 13th fret ‘Eb’, and then the 15th fret ‘F,’ sound good, then you have the outline of the Eb Major scale.
So the song is either in the Key of Eb Major, or it’s in the Key of C Minor, which is the relative minor of Eb Major.
Essentially, how you determine whether it’s in a Minor or Major key is just by listening to it. If it sounds kind of sad or down, then it’s probably a Minor Key.
Additionally, if you play a C Minor chord or just a regular ‘C’ note, and it sounds like the very first note of the song is that note or that chord, then you know you’re in the Key of C Minor.
YouTube Video Tutorial
I really hope this was helpful to you. It really isn’t quite as complicated as it seems. As I mentioned above, just memorize what the key signatures are called, F, C, G, A, etc, and then memorize the modes in one key signature, ideally, C Major, and then you can move them around as you see fit.