1 Music Theory – 1D Triads

In this lesson we will learn:

To create the four main types of triads :





The “basic” triads are the foundation of harmony. There are four types of triads possible : major, minor, diminished and augmented. Triads are just two sets of triad intervals stacked on top of each other. The quality (type) of triads determines the quality (type) of the chord. I have provided several ways to learn the different types of triad chord types.

Major triad

C major chord

Semitone approach

Start on any key and use the following guideline of semitones:


Stacked thirds approach (M=major / m=minor)

Start on any note and use the following sequence of thirds:


Numeric approach

Start on any key and use the following numeric pattern:


Common ways of writing the chord:

C, (CM rare)

NOTE: These approaches apply to all chords. I have provided a table at the end that has all the information needed so you can check if you got them right. 

Minor triad

C minor chord

Common ways of writing the chord:

Cm , C-, Cmin

NOTE: The major and minor triads are the most commonly chords used triads. Learning these in all keys should be enough if you are staring out. The ones below are less frequently used and fill the “four main” triad categories (major, minor, diminished, augmented). They are however used when constructing larger chords (by adding another bass note to the chord).

Diminished triad

Cdim chord

Common ways of writing the chord:

Cdim, Co, (C-)* (Cb5 rare)

* Not recommended since could be confused with C minor

Augmented triad

Caug chord

Common ways of writing the chord:

Caug, C+, C#5

Triads chord table

ChordIn CSemitonesThirdsN. Pattern

Additional information available:

Additional information available on the subject. It covers a more extensive list of possible triads. Uncommon and rare triads are mostly used as part of two handed chords.

(c) Sibil Yanev 2019