Types of Triads Explained: Major, Minor, Diminished, and Augmented

A triad is a three-note chord built from a root, third, and fifth. In music theory, the four main types of triads are major, minor, diminished, and augmented. These triad types are created by changing the intervals between the three notes, which changes the character and sound of the chord.

For example, starting with a C major triad:

C – E – G

Changing only one or two notes can create completely different triads:

• C minor: C – E♭ – G
• C diminished: C – E♭ – G♭
• C augmented: C – E – G♯

Understanding triads is essential because they form the foundation of many larger chords, chord progressions, and harmonic structures used in music.

What Is a Triad in Music Theory?

A triad is the simplest type of chord that contains three different notes played together.

The three parts of a triad are:

• Root: The note that gives the chord its name
• Third: The note that determines whether the chord sounds major or minor
• Fifth: The note that provides stability and completes the chord

For example:

C major triad

• C = root
• E = third
• G = fifth

Together:

C – E – G

All triads are chords, but not all chords are triads. A chord can contain more than three notes, such as seventh chords, ninth chords, and other extended chords.

You can learn more about how chords are created from notes in this guide on how chords are built.

How Triads Are Built

Triads are created by stacking intervals above a root note.

The basic process is:

Choose a root → Add a third → Add a fifth

Root Note

The root is the starting point of the triad.

Examples:

• C major begins with C
• G minor begins with G
• A diminished begins with A

The root determines the name of the chord.

Third Interval

The third is the most important note for determining the quality of a triad.

A major third creates a major triad.

Example:

C → E

A minor third creates a minor triad.

Example:

C → E♭

This single interval change can completely transform the emotional quality of a chord.

Fifth Interval

The fifth adds stability and helps define the final sound of the triad.

A perfect fifth creates a stable sound, while a lowered or raised fifth creates diminished or augmented qualities.

The Four Main Types of Triads

Major Triads

A major triad has a bright and stable sound.

Formula:

1 – 3 – 5

Example:

C major:

C – E – G

Structure:

• C = root
• E = major third
• G = perfect fifth

Major triads are among the most commonly used chords in music.

They are frequently used in:

• Pop songs
• Classical music
• Rock
• Folk music

You can explore more about this chord type in the guide to major triads.

Minor Triads

A minor triad has a darker or more emotional quality compared with a major triad.

Formula:

1 – ♭3 – 5

Example:

C minor:

C – E♭ – G

The difference between C major and C minor is only the third:

C major:

C – E – G

C minor:

C – E♭ – G

Lowering the third by one semitone changes the chord quality from major to minor.

Learn more about this structure in the guide to minor triads.

Diminished Triads

A diminished triad has a tense and unstable sound.

Formula:

1 – ♭3 – ♭5

Example:

C diminished:

C – E♭ – G♭

Compared with a minor triad, the fifth is lowered by one semitone.

C minor:

C – E♭ – G

C diminished:

C – E♭ – G♭

Because of this unstable interval structure, diminished triads are often used to create musical tension that resolves to another chord.

You can learn more about diminished harmony in this guide on diminished chords explained.

Augmented Triads

An augmented triad has a raised fifth, creating a unique and unstable sound.

Formula:

1 – 3 – ♯5

Example:

C augmented:

C – E – G♯

It is created by taking a major triad and raising the fifth note by one semitone.

C major:

C – E – G

C augmented:

C – E – G♯

Augmented triads are often used to create tension and unusual harmonic movement.

You can explore this chord type further in the guide to augmented triads.

Triad Comparison Table

Type	Formula	Example	Sound Character
Major	1 – 3 – 5	C – E – G	Bright and stable
Minor	1 – ♭3 – 5	C – E♭ – G	Dark and emotional
Diminished	1 – ♭3 – ♭5	C – E♭ – G♭	Tense and unstable
Augmented	1 – 3 – ♯5	C – E – G♯	Floating and unresolved

How Small Changes Create Different Triads

One of the most useful ways to understand triads is to see how changing intervals changes the chord.

Starting with C major:

C – E – G

Lower the Third

C – E♭ – G

Result:

C minor

Lower the Third and Fifth

C – E♭ – G♭

Result:

C diminished

Raise the Fifth

C – E – G♯

Result:

C augmented

This shows that triad types are not random. They are created by specific interval relationships.

How Musicians Use Triads

Creating Harmony

Triads provide the harmonic foundation of many songs.

A melody may be built from individual notes while triads support it underneath.

Building Chord Progressions

Many common chord progressions are made using triads.

Example:

C major → G major → A minor → F major

Each chord creates movement and emotion within the song.

Arranging Music

Musicians use different triads to create different moods:

• Major triads for stability
• Minor triads for emotion
• Diminished triads for tension
• Augmented triads for unusual color

Common Mistakes When Learning Triads

Confusing Triads With All Chords

A triad is a specific type of chord containing three notes.

Other chords may contain four or more notes.

Memorizing Shapes Without Understanding

Learning chord shapes on piano or guitar is useful, but understanding the intervals behind them makes it easier to create and modify chords.

Ignoring Intervals

The quality of a triad depends on the relationship between its notes.

Understanding intervals makes it easier to recognize why chords sound different.

Frequently Asked Questions

What are the four main types of triads?

The four main triad types are major, minor, diminished, and augmented.

How many notes are in a triad?

A triad contains three different notes: the root, third, and fifth.

Are all triads chords?

Yes. Every triad is a chord, but not every chord is a triad because many chords contain more than three notes.

What is the difference between major and minor triads?

The main difference is the third interval. Major triads use a major third, while minor triads use a minor third.

Why are triads important in music?

Triads are the foundation of harmony and are used to build chord progressions, accompaniment patterns, and larger chord structures.