Before looking at the most important keyboard chords, it's useful to know what chords are. They are three or more notes played together. But what kind of notes?
There are twelve different kinds of notes. These notes repeat up and down from Middle C (near the center) on the keyboard.
There are "natural" notes: A, B, C, D, E, F, G
There are "sharp" notes: A♯, B♯, C♯, D♯, E♯, F♯, G♯
There are "flat" notes: A♭, B♭, C♭, D♭, E♭, F♭, G♭
Each sharp note is the next note above the natural note, and each flat note is the next one below the natural note. As you can see on the keyboard below, some notes have two names.
It's also important to know that there are no sharp/flat notes between B to C and E to F.
How do we make chords?
Major Chords
To play a major keyboard chord, for example, put your right thumb on C, count up four notes and put another finger on E then count up three more notes and put a third finger on G. You can do the same with any other note.
Major chords use three kinds of notes from the major scale (more about music scales):
• 1st note (Root)
• 3rd note
• 5th note
And all other chords are derived from these notes.
This is what a C major chord looks like for example:
To make a major triad (major chord), count up four notes from the Root note (not counting the Root itself). Then count up three more notes from the 3rd to find the 5th note. It means that you don't need to memorize the notes in a chord. If you know the root, you know the other notes you have to play.
Advanced Chords
All other keyboard chords are modifications or extensions of the major chords we talked about in the previous section. What you always do is start with a major chord then follow the instructions given in the chord name.
Most songs in contemporary music contain major chords (triads), minor chords and seventh chords. If you know how to make these, you can play most of the songs out there.
Minor Chords
You use minor chords when you'd like to play melancholic music. How do you make minor keyboard chords? Just substitute the 3rd note in the major chord with the flatted 3rd note, i.e. Root, 3♭, 5th. So if you see an "m" in any chord name, e.g. "Cm ", you'll know that all you have to do is flat the 3rd. Take a look at the example below:
Seventh Chords
Seventh chords have a kind of pulling sound. They are made by adding a 7th flatted note to a chord, i.e. two notes below the Root. They are easy to recognize, e.g. "C7". If you add a 7th note and not a 7♭ note, it's called a "dominant 7th".
Major 7th Chords
In major 7th chord titles there is a capital "M". In 7th chords there is no "M". So for example, CM7 would consist of C, E, G, B. The 7th note is one note below the Root.
6th Chords
You make a 6th chord by adding the 6th note to the chord. Example: C6 would consist of C, E, G, A. The 6th note is three notes below the Root.
Suspended Chords
Suspended keyboard chords have a "sus" in the chord title. You make them by moving up 1 note from the 3rd and substitute the original 3rd with it. For example, Csus would consist of a C, F, G (because we substituted the original 3rd, E with F that is one note up).
Flat 5 Chords
In flat 5 chords you flat the 5th note. So if you see a chord title like Cflat5 or C-5, you'll know that it means C, E, G♭.
Augmented Chords
You'll know it's an augmented chord when you see "aug" or "+" in the chord title. You make the augmented keyboard chords by using 5♯ instead of 5th. For example, Caug would consist of C, E, G♯ .
9th Chords
If you see a "9" in a chord title, you'll have to know immediately that first you'll need to add the 7♭ note and the 9th note to the base chord.
11th Chords
If you see an "11" in a chord title, you'll have to recognize that first you'll need to add the 7♭, the 9th note and then the 11th note to the base chord.
13th Chords
If you see a "13" in a chord title, you'll have to know that first you'll need to add the 7♭, the 9th, the 11th note and the 13th note to the base chord.
Diminished or Half Diminished Chords
In a diminished chord, you flat the 3rd and the 5th. If you diminish a C chord, you'll get C, E♭, G♭.
Diminished 7th Chord
In this kind of chord, you lower every note except the Root. If we take a C chord as an example, we'll get C, E♭, G♭, B♭♭. (In a seventh chord, the last note would be B♭♭ and it's the same as the 6th note.) B double flat means an A.
Chords with Added Notes
The "add" part of a chord title means that you'll have to add a note to it. For example, a Cadd11 means that you'll need to add an 11th note to the C chord.
The different chord symbols we've talked about so far can appear "in bulk". For instance, if you see a Csus7+, you'll have to make the 3rd sharp (sus), add the 7♭ because of the "7" and sharp the 5th because of the "+".
Chord Inversions
If we take major keyboard chords, you can make the first inversion by moving the Root up. It means, that you play the 3rd, the 5th and the Root. Example: s C major chord first inversion is E, G, C.
In case of second inversion, you move the 3rd to the top, which gives you 5th, Root and 3rd. Example: C major chord second inversion is G, C, E.
Summary of Piano Chord Theory
When you make keyboard chords, you always start by playing a Root, a 3rd, and a 5th. Then you modify this major chord according to the chord theory rules:
▪ minor chord ("m") - change the 3rd to 3♭
▪ suspended chord ("sus") - change the 3rd to 3♯
▪ flat 5 chord ("-5") - change the 5th to 5♭
▪ augmented chord ("+") - change the 5th to 5♯
▪ major 7th chord ("M7") - add the 7th note
▪ dominant 7th chord ("7") - add the 7♭ note
▪ sixth chord ("6") - add the 6th note
▪ ninth chord ("9") - add the 7♭ and the 9th note
▪ eleventh chord ("11") - add the 7♭, the 9th and the 11th note
▪ thirteenth chord ("13") - add the 7♭, the 9th, the 11th and the 13th note
▪ added notes ("add") - add the 6th note
▪ diminished chords ("dim") - flat the 3rd and the 5th
▪ diminished 7th chords ("dim7") - flat every note except the Root
Now you're able to play most of the keyboard chords out there. You can also play the combinations of these chords above, and there are thousands of them. If you wish to learn even more about keyboard chords, I recommend Chordmaster Chord Theory for Keyboard
and The Complete Book of Scales, Chords, Arpeggios and Cadences
. Have fun!
. I also recommend having a full piano chords chart on your wall, like this 
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to find out the answers to these questions.