Related keys stay close
Move clockwise from C to G and only one note changes: F becomes F-sharp. This makes neighboring keys natural places for modulation, comparison, and gradual transposition practice.
Free interactive music theory guide
Learn music theory by seeing, hearing, and using it.
Start with the circle of fifths, then connect keys, chords, cadences, scales, and ear training in one practical path. Every idea leads to something you can play, sing, compare, or reuse.
- Visual relationships
- Playable examples
- Short practice tasks
Selected key
C
major
Choose a key on the circle. Use the arrow keys to move between neighboring keys, then listen to its tonic or V–I cadence.
- Key signature
- 0 ♯ / ♭
- Relative minor
- A
- Dominant (V)
- G
- Neighboring keys
- ← F G →
C major selected.
Clockwise motion organizes keys by rising fifths. Counterclockwise motion follows the dominant-to-tonic resolution heard in countless songs.
Lesson 1 · The essential map
What the circle of fifths actually tells you
The circle is useful when it explains musical distance and movement. Adjacent keys share most of their notes, dominant chords resolve toward neighboring tonics, and a single exercise can travel through all twelve keys in a logical order.
Dominants point home
Read the circle counterclockwise to see G resolving to C, C resolving to F, and F resolving to B-flat. That root motion gives V–I and ii–V–I cadences their clear direction.
All twelve keys become a route
Choose one scale, chord voicing, cadence, or melody fragment. Move one step around the circle after each repetition so the material changes key without changing its musical purpose.
Ten-minute exercise
One lap, one musical idea
Keep the rhythm and shape stable while the key changes. Slow, accurate movement around the circle builds useful transposition skill faster than playing twelve unrelated examples.
- Play a C major triad and sing its root.
- Move clockwise to G, then D, then A.
- Return counterclockwise and hear each V–I pull.
- Repeat with a ii–V–I or a short melody.
Modal families
Scale and Mode Relations
Read modes as rotations of a pitch collection, with degree, rotation index, and formula.
first mode of harmonic minor
Harmonic Minor
Harmonic minor starts on degree I of the harmonic minor scale.
1
1
2
2
3
b3
4
4
5
5
6
b6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
second mode of harmonic minor
Locrian ♮6
Locrian natural 6 starts on degree II of the harmonic minor scale.
1
1
2
b2
3
b3
4
4
5
b5
6
6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
third mode of harmonic minor
Ionian ♯5
Ionian sharp 5 starts on degree bIII of the harmonic minor scale.
1
1
2
2
3
3
4
4
5
#5
6
6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
fourth mode of harmonic minor
Dorian ♯4
Dorian sharp 4 starts on degree IV of the harmonic minor scale.
1
1
2
2
3
b3
4
#4
5
5
6
6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
fifth mode of harmonic minor
Phrygian Dominant
Phrygian dominant starts on degree V of the harmonic minor scale.
1
1
2
b2
3
3
4
4
5
5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
sixth mode of harmonic minor
Lydian ♯2
Lydian sharp 2 starts on degree bVI of the harmonic minor scale.
1
1
2
#2
3
3
4
#4
5
5
6
6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
seventh mode of harmonic minor
Super Locrian Diminished
Super Locrian diminished starts on degree VII of the harmonic minor scale.
1
1
2
b2
3
b3
4
b11
5
b5
6
b6
7
bb7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
first mode of the major scale
Major (Ionian)
Ionian starts on the first degree of the major scale.
1
1
2
2
3
3
4
4
5
5
6
6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
second mode of the major scale
Dorian
Dorian starts on the second degree of the major scale.
1
1
2
2
3
b3
4
4
5
5
6
6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
third mode of the major scale
Phrygian
Phrygian starts on the third degree of the major scale.
1
1
2
b2
3
b3
4
4
5
5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
fourth mode of the major scale
Lydian
Lydian starts on the fourth degree of the major scale.
1
1
2
2
3
3
4
#4
5
5
6
6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
fifth mode of the major scale
Mixolydian
Mixolydian starts on the fifth degree of the major scale.
1
1
2
2
3
3
4
4
5
5
6
6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
sixth mode of the major scale
Natural Minor (Aeolian)
Aeolian starts on the sixth degree of the major scale.
1
1
2
2
3
b3
4
4
5
5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
seventh mode of the major scale
Locrian
Locrian starts on the seventh degree of the major scale.
1
1
2
b2
3
b3
4
4
5
b5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
first mode of melodic minor
Melodic Minor
Melodic minor starts on degree I of the melodic minor scale.
1
1
2
2
3
b3
4
4
5
5
6
6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
second mode of melodic minor
Dorian ♭2
Dorian flat 2 starts on degree II of the melodic minor scale.
1
1
2
b2
3
b3
4
4
5
5
6
6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
third mode of melodic minor
Lydian Augmented
Lydian augmented starts on degree bIII of the melodic minor scale.
1
1
2
2
3
3
4
#4
5
#5
6
6
7
7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
fourth mode of melodic minor
Lydian Dominant
Lydian dominant starts on degree IV of the melodic minor scale.
1
1
2
2
3
3
4
#4
5
5
6
6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
fifth mode of melodic minor
Mixolydian ♭6
Mixolydian flat 6 starts on degree V of the melodic minor scale.
1
1
2
2
3
3
4
4
5
5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
sixth mode of melodic minor
Locrian ♮2
Locrian natural 2 starts on degree VI of the melodic minor scale.
1
1
2
2
3
b3
4
4
5
b5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
seventh mode of melodic minor
Altered Scale
Altered scale starts on degree VII of the melodic minor scale.
1
1
2
b2
3
b3
4
3
5
b5
6
b6
7
b7
C
D♭
D
E♭
E
F
F♯
G
A♭
A
B♭
B
The JolyMusic learning loop
Turn every theory idea into four actions
Definitions become memorable when the eye, ear, instrument, and creative decision all describe the same relationship.
-
1
See the relationship
Locate the key center, chord function, interval shape, or rhythmic pattern before adding detail.
-
2
Hear its direction
Listen for stability, tension, color, and resolution instead of identifying symbols alone.
-
3
Play one clear example
Use a small voicing, scale fragment, or sung line that makes the relationship unmistakable.
-
4
Reuse it musically
Transpose, vary, arrange, or place the idea inside a progression so it becomes working vocabulary.
Guided Theory Lab lessons
Continue from the map into real musical situations
These lessons form a focused learning cluster: start with the circle, study harmonic motion, train the ear, then expand your scale and style vocabulary.
Circle of Fifths Interactive Guide
Use the circle as a practice clock for scales, cadences, modulation, and root-motion ear training.
Why ii–V–I Works
Follow setup, dominant pressure, guide-tone motion, and tonic arrival through a cadence musicians use everywhere.
Hear Tension Before Naming the Chord
Build a reliable listening process around stability, tendency tones, bass direction, and expected resolution.
A Practical Visual Explanation of Modes
Understand modes as different tonal centers and characteristic colors, not as seven memorized scale formulas.
Jazz Cadences to Practice in Every Key
Compare major, minor, backdoor, tritone-substitution, and turnaround routes while keeping function audible.
Hirajoshi: Five Notes, Strong Image
Explore a compact pentatonic collection whose interval pattern creates immediate melodic identity.
Neo-Soul Harmony Without Losing the Song
Add extensions, smooth voice leading, and harmonic color while preserving a progression listeners can follow.
A realistic practice plan
Four weeks from diagram to musical reflex
Practice for fifteen to twenty minutes, four days per week. Keep one notebook or saved workspace and record what you can hear and play without looking.
Keys and fifths
Name the twelve keys, play major triads around the circle, and compare adjacent key signatures.
Goal: one accurate circle lapCadences and guide tones
Play V–I and ii–V–I in six keys. Sing the leading tone and seventh as they resolve.
Goal: hear arrival before naming itModes and melody
Compare major, Dorian, Mixolydian, and one pentatonic color over a repeated tonal center.
Goal: identify each characteristic toneCreate and review
Write an eight-bar progression, transpose it to a neighboring key, and record one melodic variation.
Goal: reuse theory in your own musicFree interactive tools
Test the lesson with sound and visual feedback
Move from reading to action. Open a tool, make one choice, listen, and describe what changed.
Harmony explorer
Inspect progressions, tonal centers, and harmonic relationships visually.
Open tool →
Chords and scales
Compare formulas, notes, colors, and playable tonal material.
Open tool →
Ear training
Practice recognition through repeatable listening challenges.
Open tool →
Audio key and scale detector
Analyze recorded or live audio and compare the estimate with your ear.
Open tool →
Common questions
How to learn music theory effectively
Where should a beginner start with music theory?
Start with one major key, the intervals inside its scale, and the I, IV, and V chords. Use the circle of fifths to add neighboring keys gradually instead of trying to memorize every topic at once.
Do I need to memorize the circle of fifths?
Memorization helps, but use is more important. Play a short pattern around the circle, notice how accidentals change, and sing dominant-to-tonic roots. The map becomes memorable because it predicts sound.
Should I train my ear before learning chord names?
Train both together. Hear whether a sound feels stable or wants to move, then attach the chord name and function. This prevents theory vocabulary from becoming disconnected from music.
Can I use this music theory guide for free?
Yes. This guide, the linked public lessons, and several interactive JolyMusic tools can be used without creating a paid account.
How can a teacher use this learning path?
Assign one concept and one action per lesson: see the relationship, hear it, play it, then reuse it. Students can explain the result in words or submit a short recording instead of completing a definition-only worksheet.