Each note has a distance between it and any other note. This is referred to as the “interval” between two notes. You’ve probably already noticed that some white notes have a black note between them, and some don’t. Well, a “C” note provides a handy place to explain that, so put a finger onto the middle “C” on your keyboard.
The first thing you notice is that the white key to the right of that “C” note has a black key between them, and the white key to the left of it does not. So, the interval between your “C” and the white key below it is said to be a “half step”, and the interval between the “C” and the next white note above it is referred to as a “whole step”.
You probably already know that if you play only the white keys, starting on any “C” and going up, the notes are referred to as “D”, “E”, “F”, “G”, “A”, and “B”, respectively. The following statement is all you need to known to play the first chord of the song you’ve selected.
One. Three. Five.
Now, look at the letter that is indicating what chord to play first. I’m going to use a “C” chord, because you already know where the “C” note is!
Now; if we call the “C” note “#1”, then if you count up, in whole steps, you will find an “E” note is “#3”, which we will call “the third”. If you count up a one whole step from the third, and then go one half step higher, you will hit a “G” note, which we will call “the fifth”. If you play notes #1, #3, and #5 together, you will be playing a “C chord”!
But what if your song starts with a chord indicator other than “C”? The exact same principles apply!
Let’s take an “F” chord as an example. You already know how to find which note is an “F” note, so put your finger on one now.
Next, count up one whole step, (which is a “G” note), and another whole step, which gives you the “1” and the “3”, (an “A” note). Count up one whole step, then one half step, from the “A” note, (the “C” note), and that will give you the 1, 3, and 5 notes for an “F chord”!
So far, you now know that a “C chord” is played on the notes of C, E, and G, (1, 3, and 5), and an “F chord” is played on the notes F, A, and C, (likewise, 1, 3, and 5). And that really is all you need to know to figure out any chord! Locate the note that shares the name with the chord indicated, count up two whole steps, count up three more half steps, and you have that chord!
Unless the chord is written as a minor chord. (Example: “Dm” rather than “D”). To play a minor chord, all you have to do is take the “3 note”, (called a third), and drop it one-half step! And that is all you need to do to play any major or minor chord on a piano!
Just remember this: if the chord indicated has only the letter, it’s 1-3-5. If the chord indicated is a minor chord, it’s 1-b3-5. This would be a good time for you to figure out what’s in a Bbm (pronounced “bee-flat minor”) chord.
First, find Bb. You’ll find it is the highest black key before a “C” note. Two whole steps higher is a “D” note, and a one-and-one-half step above that is an “F” note, since the interval between an “E” and an “F” is only a half step. That tells you the 1-3-5, and as it’s a minor chord, play the third, (the “D” note) one half step lower. If you’re playing the right notes, it should sound gothic and mournful. In letter terms, you’re playing a Bb, a Db and an F.