This is a very common question amongst beginning guitarists. Often, these new players see thick guitar chord books or one of those chord chart posters with seemingly hundreds of chord diagrams, and they become overwhelmed. But guess what? It is true. All you really need to know are 3 chords. Let us find out which ones and why.

When songs are written, they are written in something called a key. A key is represented by a letter on the musical scale, for example the key of D, or the key of G. Within the key, and therefore the song, there are three primary chords. These are the chords you need to know. If you want to strum your guitar and sing along with your favorite songs, all you need to do is find out these primary chords.

What you will then do is listen to the song and play those three chords along with the song. You will very soon figure out the order. It's even better if you have the song chords in front of you. Just go online and look for tabs or chords for the song. Often, you will see the song lyrics with chords above certain words in the lyrics. This indicates where you will change from playing one chord to the next. (The chords, like keys, are represented by letters in the musical scale such as A or F.) From here on out, all you have to do is figure out the strum pattern of the song.

At this point you are probably thinking, Wait, songs are written in different keys; I then have to know the primary chords for every key, right? This is a very intelligent question. The answer; however, is no. What we will look at now is how to find the primary chords for a key. Then I will show you how to transpose those chords to any key.

This point is best illustrated with an example. Remember there are three primary chords to a key. We will use the key of D in this example. The three primary chords in this key are D, A, and G. How do I know this? I used a simple formula that works for any key. What you do is list out the major musical notes (A, B, C, D, E, F, G) starting with the key letter. In this case it is D, E, F, G, A, B, C. The formula is 1, 4, 5. Start with D as 1 then count to the fourth and fifth letters. So you have D, G, and A as the three primary chords. This process works for any key.

Suppose you only learn these 3 chords and you find a song with the primary chords F, C, and G. What key is this? Let's use the process above to find out. Well F and G follow each other in the alphabet, so they are obviously the fourth and fifth letters. Therefore, C is the first letter and the key. Now, how do you, who only know D, G, and A chords, play a song in the key of C? Simple. Transpose the chords by using the formula. In the key of C, the 1, 4, 5 formula gives C, F, and G. In the key of D, the 1, 4, 5 formula gives D, G, and A. So in place of C, play D. In place of F, play G. In place of G, play A. Then just strum along to the song.

The cool thing is you can do this for any chords in key. Whenever you see chords different from those you know, simply transpose them to the three chords you do know. Of course, the more chords you know, the better and more diverse guitarist you will be. You should make an effort to learn and use as many chords as possible. But to strum along with just about any song, you only need to know three chords.