What a chord is
Chord is the sound of three or more different notes played together. The simplest chord has three notes and is called a triad:
- Root (1): the note that gives the chord its name.
- Third (3): the note that decides whether it's major or minor.
- Fifth (5): the note that adds body and stability.
The trick: “skip one, take one”
In the scale, starting from the root, take a note, skip the next, take the one after. In C: C (D) E (F) G. Done: C–E–G is the chord of C major (C).
This works because chords are made of stacked thirds: C→E is a third, E→G is another third.
Major or minor: the size of the thirds
What changes between a major and a minor chord is the order of the thirds:
| Type | Formula | Thirds | In C | Chord symbol |
|---|---|---|---|---|
| Major | 1 – 3 – 5 | major + minor (4 + 3 half steps) | C E G | C |
| Minor | 1 – ♭3 – 5 | minor + major (3 + 4) | C E♭ G | Cm |
| Diminished | 1 – ♭3 – ♭5 | minor + minor (3 + 3) | C E♭ G♭ | C° or Cdim |
| Augmented | 1 – 3 – ♯5 | major + major (4 + 4) | C E G♯ | C+ or Caug |
Only the E went down a half step.
Learn by playing. In Dedilhado Vivo you see where each finger presses, play for real and the app checks you through the microphone. Free, no sign-up.
Open the free app →Building on any note
Use the half-step ruler: from the root, count 4 half steps for the major third (or 3 for the minor) and 7 half steps for the fifth. Examples:
| Chord | Root | Third | Fifth |
|---|---|---|---|
| D (D major) | D | F♯ | A |
| Dm (D minor) | D | F | A |
| E (E major) | E | G♯ | B |
| Em (E minor) | E | G | B |
| G (G major) | G | B | D |
| A (A major) | A | C♯ | E |
| Am (A minor) | A | C | E |
| F (F major) | F | A | C |
And on guitar, why does the chord have 6 notes?
The guitar has six strings, but the chord still has only three different notes: they show up repeated in octaves. In E minor (Em) with all six strings, the notes are E, B, E, G, B, E: just E, G and B.
| String | 6ª | 5ª | 4ª | 3ª | 2ª | 1ª |
|---|---|---|---|---|---|---|
| Em (E minor) | E (1) | B (5) | E (1) | G (♭3) | B (5) | E (1) |
| C (C major) | × | C (1) | E (3) | G (5) | C (1) | E (3) |
In the guide to guitar you can see the diagrams, and in the app the neck shows each finger in color.
Inversions: same triad, different bass note
The notes of a chord can appear in any order. When the lowest note isn't the root, we have an inversion:
| Position | Bass note | Notes (from bottom to top) | Chord symbol |
|---|---|---|---|
| Root | C | C E G | C |
| 1st inversion | E (third) | E G C | C/E |
| 2nd inversion | G (fifth) | G C E | C/G |
The slash in a chord symbol (C/E) means “C chord with E in the bass”. See more in how to read chord symbols.
How each type sounds
- Major: open, happy, resolved.
- Minor: darker, melancholic.
- Diminished: tense, unstable, great as a passing chord.
- Augmented: mysterious, “floating”, common in suspense soundtracks.
Now put the theory into your fingers
In Dedilhado Vivo you learn flute, guitar, violin or piano by seeing each finger on the screen, and the app listens to you play through the microphone.
Practice theory in the free appFrequently asked questions
How is a major chord built?
The root, the major third (4 half steps up) and the perfect fifth (7 half steps up). Example: C = C, E, G.
What's the difference between a major and a minor chord?
Just the third. In minor it's a half step lower: C = C E G; Cm = C E♭ G.
How many notes does a chord have?
A triad has three different notes. Seventh chords have four, and ninth chords five. On the guitar, notes can repeat across several strings.
What does C/E mean in a chord chart?
C major chord with E in the bass (first inversion).