In this video Simon walks you through the most common keys on classical guitar and why we hear these keys more frequently than others. To follow along, download our free Circle of Fifths Diagram at the link below.

Common Keys on Classical Guitar

Have you ever wondered why we always seem to play in the same keys on classical guitar? Em, C Major, A minor, G Major, D Major… These are keys we hear all the time on the guitar. But what about Bb Major? Eb Major? Or G minor? There’s a good reason why we don’t hear these latter keys on the flat side of the circle of fifths very often. So let’s break down why some keys are more prevalent on classical guitar than others.

Open Strings

The biggest reason why composers choose certain keys is the usefulness of the open strings on the classical guitar. Open strings are resonant and they allow more fingering options as well. And another thing open strings help us avoid is using too many barres. The barre is a technically difficult technique on the guitar and it can also drain the hand. And significantly keys on the flat side of the circle of fifths require a lot of barres because we simply can’t use as many open strings with flat keys.

C Major

So let’s take a look at the Circle of Fifths. In the key of C Major, right at the top of the circle of fifths, the notes in that scale and the chords that come out of the scale can all be used on the open strings. The open string notes on the guitar are EADGBE, all notes that we find in the C Major scale. Thus, there is a lot of usefulness to the key of C Major because it can utilize all of the guitar’s open strings.

E minor

Likewise, E minor is a popular key because it has so many open strings we can utilize. E minor only has one sharp, F# — although it also frequently makes use of D# — but it still has many open-string advantages. The root of the chord of E minor, E, is on the open sixth string. That same note, up two octaves, is also found on the open first string. And the important fifth scale degree of the Em chord, which is B, is on the open second string. In fact, we can play the whole E minor chord just by playing the open 6th, 3rd, 2nd, and 1st strings. Thus, E minor is a very useful key on the guitar.

Flat Keys

C minor

But why do we not hear flat keys as often? Well, C minor has three flats: B flat, E flat, A flat. Thus, we lose the usefulness of four open strings: B on the 2nd string, E on the 6th string, and E on the 1st string, as well as A on the 5th string. Add to that the fact that we have to play so many barres because we can’t play as many open strings, and we end up with more technical challenges. And arguably we lose some resonance with so many barres. Thus, the flat side of the circle of fifths is less useful on the classical guitar.

Ensemble Playing

When you play music with other instrumentalists or singers, you’ll find a lot of keys not as familiar on the guitar. Flat keys are much more common on the clarinet or brass instruments, or even with vocal music. But as we’ve seen they’re not as common on the guitar, and thus not only are they technically more challenging but they are also more difficult to sight read for that reason.

One thing we can do to quickly adapt to these situations is to use a capo. For instance, if your singer’s music is in the difficult-to-impossible key of Db Major, you can put a capo on the 1st fret and play as though you’re in the key of C Major on the guitar. Everything will sound at the pitches of Db Major.


So we hope this has helped clear up why some keys are just more common on the guitar than others. To make finding any key signature really easy, download our free Circle of Fifths Diagram at the link below!

There are many more lessons on theory that are practical and applicable to the classical guitar at Classical Guitar Corner Academy. Join CGC Academy today!