1.What is a Chord? 2.Major & Minor Triads 3.Inversions 4.Seventh Chords 5.Extended Chords 6.Suspended Chords 7.What is a Progression? 8.Common Progressions 9.Cadences 10.Borrowed Chords 11.Secondary Dominants
Lesson 2

Major & Minor Triads

How to build major and minor triads, the difference between them, and how they sound. Hear and compare chords with interactive examples.

By the end: You can build major and minor triads from any root and describe the semitone change that distinguishes them.

Major and minor triads are two basic chord qualities built from a root, third, and fifth. They appear in many styles because the formulas are easy to transpose and recognise.

Both use three notes: root, third, and fifth. The only difference is the third.

The major triad

A major triad uses a major third (4 semitones from the root) and a perfect fifth (7 semitones from the root). In a simple root-position example, the major third gives the triad a more open, settled quality. The instrument and surrounding harmony still affect the result.

C Major - C, E, G

Major triad formula

Root + 4 semitones -> Major 3rd + 3 semitones -> Perfect 5th

The minor triad

A minor triad uses a minor third (3 semitones from the root) and a perfect fifth (7 semitones - same as major). In a simple root-position example, the minor third gives the triad a more compact, subdued quality. It is not tied to one emotion or genre.

C Minor - C, Eb, G

Minor triad formula

Root + 3 semitones -> Minor 3rd + 4 semitones -> Perfect 5th

The one-note difference

Same root, same fifth. The third moves by one semitone. That small change is enough to change the triad's quality while the root remains fixed.

The diminished triad

A diminished triad uses a minor third and a diminished fifth (6 semitones from root). Both intervals are close to the root, so the chord often sounds tense and unstable, especially when it functions as a leading chord toward a more stable harmony.

C Diminished - C, Eb, Gb

Diminished triad formula

Root + 3 semitones → Minor 3rd + 3 semitones → Dim 5th

The augmented triad

An augmented triad uses a major third and an augmented fifth (8 semitones from root). It sounds dreamy and unresolved - like something reaching upward. Common in film scores and jazz.

C Augmented - C, E, G#

Augmented triad formula

Root + 4 semitones → Major 3rd + 4 semitones → Aug 5th

Power chords

A power chord is just the root and the fifth - no third at all. Without a third, there's no major or minor quality. It's neither sweet nor sour - just raw, direct energy. That's why they dominate rock, punk, and metal.

C5 (power chord) - C, G

Power chords are written with a 5 after the root (C5, G5, A5). They sound huge through distortion because the simple interval doesn't create muddy overtones.

Try it

Build a C major triad from the formula, then lower only E by one semitone to make C minor. Repeat the same exercise from A. Check that the root and fifth stay fixed while the third changes.

Major: root + 4 + 3 semitones. Minor: root + 3 + 4 semitones.

Why this matters

Major and minor triads are the building blocks of everything else. Seventh chords, Extended chords and progressions build on these interval patterns. Learn to hear the third and fifth here, and you have a reference point for more complex voicings.

Key takeaway

Four triad types: major, minor, diminished, and augmented. Their interval formulas determine the chord quality; context and voicing shape the result. Power chords drop the third for raw energy. The third determines a chord's character.

Next: rearranging chord notes so they flow smoothly between chords - inversions.

Hear major and minor side by side

Tap each pair to hear how the same root changes character.

Generate triads in any key

Starts builds chord progressions using major and minor triads automatically.