Music Theory — Interactive Guide

⭐ Start Here — Beginner's Guide

New to music theory? This page explains the big ideas so every other section makes sense. Read this first, then explore the tabs above.

🎹 New: The Live Keyboard

A piano is now docked at the bottom of your screen. Every time you press a ▶ Play button anywhere in this guide, the exact keys you'd need to press light up — gold for the root note, crimson for the rest. Scales light up step by step, and chord progressions show each chord as it sounds. It even works with the sound muted, and you can click its keys directly to explore.

Try it now:

▶ One Note (middle C) ▶ A Chord (C major) ▶ A Scale (C major) ▶ A Progression (I–IV–V–I)

What Is Music Theory?

Music theory is the language musicians use to describe why certain notes, chords, and rhythms sound the way they do. It won't tell you what to play — it explains what you're already hearing.

Think of it like learning grammar after you already speak a language. You don't need theory to make music, but it helps you understand, communicate, and grow much faster.

The 12 Notes — The Chromatic Scale

Western music uses 12 notes, each a semitone (half-step) apart. After 12 steps, you're back to the same note — just one octave higher. These 12 notes repeat forever up and down your instrument.

💡 TIP: C# and D♭ are the same pitch — just two different names. This is called an enharmonic equivalent. Which name you use depends on the key you're in.

Semitones & Tones (Half-Steps & Whole-Steps)

SEMITONE (half-step)

The smallest step — moving to the very next key on a piano (white or black). C → C# is a semitone. E → F is also a semitone (no black key between them).

TONE (whole-step)

Two semitones combined. C → D is a whole tone (you skip C#). A whole tone = 2 half-steps.

What Is a Scale?

A scale is a specific selection of notes from the 12, arranged in a pattern of steps. The pattern of whole steps (W) and half steps (H) determines the scale's character — and crucially, it's the same pattern in every key. That's why you can play a major scale starting on any note.

The Major scale uses the pattern W – W – H – W – W – W – H. Starting on C, that gives you the 7 white keys: C D E F G A B. Below, the gaps between notes show whether each step is a Whole step (2 keys) or Half step (1 key):

💡 TIP: The root note (note 1) gives the scale its name. C Major starts on C. G Major starts on G — same W-W-H-W-W-W-H pattern, different starting point. See the Scales & Modes tab for every scale's step pattern and an interactive piano.

What Is a "Key"?

A key is the home base of a piece of music. When a song is "in the key of C major," it mostly uses the notes from the C Major scale, and the note C feels like "home" — stable and resolved.

You can think of the key as the tonal center that everything else orbits around.

What Is a Chord?

A chord is 3 or more notes played at the same time. The most common chords are triads — built by stacking every other note of a scale.

MAJOR CHORD

Root + Major 3rd + Perfect 5th. Sounds bright and happy.

C major = C + E + G

MINOR CHORD

Root + Minor 3rd + Perfect 5th. Sounds darker and sadder.

A minor = A + C + E

💡 TIP: Chords built from a scale are called diatonic chords — they all belong to the same key. The Major Grid and Minor Grid tabs show all of them at once.

Roman Numerals — Why I, ii, IV, V?

Musicians number chords by their position in the scale using Roman numerals. This lets you describe a progression that works in any key.

Scale Degree	Roman	Quality	In C
1st	I	Major	C
2nd	ii	minor	Dm
3rd	iii	minor	Em
4th	IV	Major	F
5th	V	Major	G
6th	vi	minor	Am
7th	vii°	dim°	B°

💡 TIP: UPPERCASE = Major, lowercase = minor. So "I IV V" means three major chords. "i iv v" means three minor chords. The case tells you the chord quality at a glance.

How the Tabs Connect — A Learning Path

Here's a suggested order for beginners. You don't have to follow it strictly — jump around as your curiosity leads you.

Quick Glossary

Scales & Modes

A scale is a family of notes that belong together. Select a root key to see all 7 modes — each is the same notes as the major scale, but starting from a different degree, giving it a unique emotional color. The root note is highlighted in gold. Below the notes you'll see the diatonic chords that naturally fit that scale, plus each mode's step pattern.

🎹 Interactive Piano — See Any Scale

Pick a root and a scale type to light up the notes on the keyboard. The gold key is the root.

▶ Play Scale ▶ Play Root Triad

Root Scale note

Scale Step-Pattern Reference

Every scale is defined by its pattern of Whole steps (W = 2 semitones), Half steps (H = 1 semitone), and occasionally Whole-and-a-Half steps (W½ = 3 semitones). Learn the pattern once and you can play the scale in any key.

Major Key — Diatonic Chord Grid

Every key produces 7 chords that naturally belong to it — called diatonic chords. This grid shows all of them across all major keys. The pattern is always I ii iii IV V vi vii° — uppercase = Major, lowercase = minor. Chord notes are shown below each chord name. Use this to find chords that sound good together in any key.

Natural Minor — Diatonic Chord Grid

The natural minor scale uses the same notes as its relative major, but starts on the 6th degree — giving it a darker, more emotional feel. Its chord pattern is i ii° III iv v VI VII. Notice: the i, iv, and v are now minor (lowercase), and the ii is diminished. This is why minor keys feel sadder.

Dorian Mode — Diatonic Chord Grid

Dorian is a minor mode — but with a raised 6th compared to natural minor. This one note makes a huge difference: it gives Dorian a brighter, "jazzier" minor feel. Formula: 1 2 ♭3 4 5 6 ♭7. The defining sound is the IV major chord — a major chord in an otherwise minor key. Used heavily in jazz, funk, and rock (think "Scarborough Fair", Santana, Miles Davis).

Phrygian Mode — Diatonic Chord Grid

Phrygian is the darkest of the minor modes, with a ♭2 — a half-step above the root. This creates an exotic, tense sound often associated with Spanish/Flamenco music and heavy metal. Formula: 1 ♭2 ♭3 4 5 ♭6 ♭7. The ♭II major chord (the chord built on the flattened 2nd degree) is its signature — a dramatic, unexpected major chord right next to the root. Hear it in: Metallica’s “Wherever I May Roam” and traditional Flamenco guitar.

Lydian Mode — Diatonic Chord Grid

Lydian is a major mode with a raised 4th (♯4), which gives it a dreamy, ethereal, slightly "floating" quality — brighter than regular major. Formula: 1 2 3 ♯4 5 6 7. You'll hear it in film scores (John Williams uses it often) and progressive rock. The ♯4 creates a tritone against the root, which is what gives it that magical tension despite being a major mode. Hear it in: “Flying” (the E.T. theme) by John Williams, and the Simpsons theme intro.

Mixolydian Mode — Diatonic Chord Grid

Mixolydian is a major mode with a ♭7 — one note lower than regular major. This gives it a bluesy, rock feel while still sounding bright. Formula: 1 2 3 4 5 6 ♭7. It's everywhere: blues, rock, folk, Celtic music. The ♭VII major chord is its trademark — think the intro riff to "Sweet Home Alabama" or "Hey Jude."

Locrian Mode — Diatonic Chord Grid

Locrian is the most dissonant and rarely used mode. It's like natural minor but with a ♭2 and a ♭5, making the root chord a diminished triad instead of a stable minor. Formula: 1 ♭2 ♭3 4 ♭5 ♭6 ♭7. Because the home chord itself is unstable, Locrian has no true "resting point" — which is why it's used for extreme tension in metal, horror soundtracks, and avant-garde music. Rarely used in full songs; more common as a passing mode.

Triad Chord Chart

A triad is the most fundamental chord — just 3 notes: a root, a 3rd, and a 5th. There are 4 types: Major (bright), minor (dark), diminished° (tense), and augmented+ (dreamy/unsettled). Select a key to see all 7 diatonic triads and their notes — these are the chords you'll use most in that key.

7th Chord Chart

Add a 4th note (the 7th scale degree) to a triad and you get a 7th chord — richer, more complex, and essential for jazz, soul, and R&B. The Maj7 sounds lush and smooth; the Dom7 (dominant 7th) is tense and wants to resolve back to the I chord; the m7 is soulful and mellow. Select a key to see all diatonic 7th chords.

🎧 Ear Training

Train your ear: listen, then pick what you heard. This is how you go from reading theory to hearing it. Choose a difficulty, hit play, and guess — your score tracks for this session. The answer lights up on the keyboard below once you pick.

Listen, then choose below

🔎 Chord Detective

Click notes on the keyboard to build a chord — it names what you made in real time, including inversions and other ways to read the same notes. Perfect for “what is this chord I’m playing?”

—

Click some notes to start.

🎛️ Progression Playground

Build a chord progression and loop it. Pick a key, click chords to add them, drag to reorder (× to remove), then hit play and dial in the tempo. The borrowed chords come from the parallel minor — great for adding color.

Key

Diatonic chords — the 7 in this key

Borrowed — from the parallel minor

Your progression — click a chord to add · drag to reorder · × to remove

Loop Tempo 96 BPM

Scale Degrees & Their Names

Every note in a scale has a number (1–7) and a name that describes its function — what it does and where it wants to go. These names turn up all over theory, so here’s the one table that defines them.

Degree	Name	In C	What it does
1	Tonic	C	Home. Total rest — everything resolves here.
2	Supertonic	D	Mild tension, one step above home.
3	Mediant	E	Midway to the 5th — it’s what makes the key major or minor.
4	Subdominant	F	Pulls away from home; sets up the dominant.
5	Dominant	G	The strongest pull back to the tonic.
6	Submediant	A	The root of the relative minor.
7	Leading Tone	B	A half-step below home — it “leads” your ear up to the tonic.

💡 TIP: When the 7th sits a whole step below the tonic (natural minor, Mixolydian) it’s the subtonic, not the leading tone — it doesn’t pull as hard.

▶ Hear all 7 degrees + octave

Extended Chords — 9ths, 11ths & 13ths

Triads use 3 notes; 7th chords add a 4th. Extended chords keep stacking thirds past the 7th — the 9th, 11th, and 13th. These are the lush, jazzy, neo-soul colors that make a simple progression sound expensive.

The 9th — add the 2nd, an octave up

A 9th chord is a 7th chord plus the 9th (the same note name as the 2nd). The flavor depends on which 7th you start from:

▶ Cmaj9 · dreamy▶ C9 · funky▶ Cm9 · soulful

11ths & 13ths

Keep climbing: the 11th adds the 4th, the 13th adds the 6th. You rarely play every note — keep the color tones (3rd, 7th, and the extension) and drop the rest. On a dominant chord the 3rd and the natural 11th clash, so producers usually drop the 3rd or raise the 11th (♯11).

▶ C11 · no 3rd▶ C13

💡 PRODUCER TIP: Spread the notes across octaves instead of cramming them low and close — extensions get muddy down low. Root at the bottom, color tones up high.

Borrowed Chords & Modal Mixture

“Borrowing” means pulling a chord from the parallel minor (same root, minor key) into a major progression. It’s how pop songs land those surprising, emotional turns without actually changing key. In C major, you borrow from C minor:

Borrowed	Chord (in C)	Feel	Hear
iv	F minor	Bittersweet, aching — the classic “minor four”	▶
♭VI	A♭ major	Cinematic lift	▶
♭VII	B♭ major	Rock/anthemic, Mixolydian flavor	▶
♭III	E♭ major	Bold, unexpected brightness	▶

In context

▶ I – iv – I (that ache)▶ I – ♭VI – ♭VII – I

Secondary Dominants

A secondary dominant is a dominant 7th that resolves to a chord other than the tonic — it briefly treats another chord as a mini “home.” Think of it as “the V of” something. It’s the secret behind jazz, gospel, and classic R&B’s smooth surprise chords.

Put a dominant 7th a fifth above the chord you want to target, and it pulls hard into it:

Name	Chord	Resolves to	Hear it
V7/V	D7	G (the V)	▶
V7/vi	E7	Am (the vi)	▶
V7/IV	C7	F (the IV)	▶
V7/ii	A7	Dm (the ii)	▶

💡 THE GIVEAWAY: A note from outside the key that resolves up a half-step (a borrowed leading tone). E7 in C has a G♯ that pulls straight into A.

Voice Leading

Voice leading is how you move between chords — which notes stay and which move, and by how little. It’s the single biggest thing separating beginner block-chords from a connected, professional sound. The rule of thumb: keep common tones, move every other voice to the nearest note.

Same four chords (C – Am – F – G), two ways — listen to how much smoother the second one connects:

▶ Root positionevery chord leaps back to root — clunky

▶ Voice-lednotes barely move — smooth

💡 WHY IT WORKS: In the smooth version C stays put through three chords; the other voices only shift a step or two. Your ear hears one flowing line instead of four separate jumps.

Song Structure

Theory tells you which chords sound good together; structure tells you how to arrange them into a song. Here are the forms most music is built on, and what each section is for.

The sections — what each part does

Section	Its job
Intro	Set the mood and ease the listener in.
Verse	Tells the story — melody stays similar, the lyrics change each time.
Pre-Chorus	Builds tension and lifts you into the chorus.
Chorus	The hook — the biggest, catchiest, most-repeated part.
Bridge	Contrast: new chords or melody, usually once, before the final chorus.
Outro	Wind down, resolve, or fade out.

Common forms

Modern Pop / Hip-Hop

Intro · Verse · Chorus · Verse · Chorus · Bridge · Chorus · Outro

AABA (32-bar)

Two A sections, a contrasting B (the bridge), then A again. The backbone of jazz standards and older pop.

Verse–Chorus

The workhorse of pop and rock — alternate the two, drop a bridge in late for contrast.

12-Bar Blues / Strophic

A repeating fixed form (see the Blues tab), or the same music every verse (folk, ballads).

💡 BEAT TIP: Think in 4- and 8-bar blocks. Most sections are 8 or 16 bars; the chorus often reuses the verse chords but with a fuller arrangement — more layers, not more theory.

Rhythm & Groove

Time signatures give you the grid; groove is how you place notes on it. Same chords, different rhythm = a completely different feel. Each box below is one 16th note — four beats across.

Straight vs. swung 8ths

Straight 8ths are evenly spaced. Swung 8ths are long–short (a triplet bounce) — the backbone of jazz, blues, lo-fi, and boom-bap.

Straight

Swung

Syncopation

Accenting the off-beats (the “ands”) instead of the downbeats. It’s what makes a groove feel alive instead of stiff — funk, reggae, and most hip-hop live here.

A basic backbeat

Hats

Snare

Kick

Beats fall on boxes 1, 5, 9, 13. Snare on 2 & 4 is the “backbeat” that makes you nod.

💡 PRODUCER TIP: In Ableton, raise the global Groove swing amount: 50% is straight, ~60–66% gives that human, behind-the-beat pocket. A little swing on the hats goes a long way.

Transposition

Transposing means moving a whole progression or melody to a new key — to fit a singer’s range, match a sample, or change the mood. The whole trick: move everything by the same interval.

The fast way — think in numbers

If you know the Number System (see that tab), transposing is free: the numbers never change, only the key does. I–vi–IV–V is I–vi–IV–V in every key.

Worked example — same progression, two keys

▶ In C: C – Am – F – GI – vi – IV – V

▶ In G: G – Em – C – Dsame shape, up a 5th

Step by step (by hand)

1Find the interval from the old key to the new (C → G is up a perfect 5th).

2Move every chord root by that same interval.

3Keep the qualities the same — major stays major, minor stays minor.

4Respell accidentals to fit the new key signature.

💡 DAW SHORTCUT: Pitch-shifting a sample by semitones is transposing — +2 semitones = up a whole step = up a key. Watch the timbre on big shifts (formants get chipmunky); ±2–3 semitones usually stays natural.

Chord Progressions

A chord progression is a sequence of chords that forms the harmonic backbone of a song. The same progression can be played in any key — that's why we write them with Roman numerals. Select a key below to see the actual chord names and notes. Start with I–IV–V — it's the foundation of blues, rock, and country. Then try I–V–vi–IV, which drives thousands of pop songs.

Circle of Fifths

The Circle of Fifths is a map of all 12 major keys arranged so that each neighbor is a perfect 5th apart. Moving clockwise adds one sharp to the key signature. Moving counter-clockwise adds one flat. Keys next to each other share 6 out of 7 notes — making them easy to modulate between. The inner ring shows each key's relative minor (same notes, different tonal center). Click any wedge to see its diatonic chords.

🎵 HOW TO USE — MAJOR KEY

Click your major key on the outer ring
The inner ring shows its relative minor (same notes)
The chord box below shows all 7 diatonic chords
Neighboring keys (left & right) are your closest relatives for chord borrowing

🎵 HOW TO USE — MINOR KEY

Find your minor key in the inner ring (e.g. Am)
The outer ring shows its relative major (same notes — e.g. C)
Click that outer key to see all the chords available to your minor key
The i, ii°, III, iv, v, VI, VII chords all come from this same set

💡 MINOR KEY EXAMPLE: Song is in A minor? Find "Am" in the inner ring — its relative major is C. Click C on the outer ring. The chords that appear (C, Dm, Em, F, G, Am, B°) are the same chords available to A minor — just rearranged: Am=i, B°=ii°, C=III, Dm=iv, Em=v, F=VI, G=VII.

Clockwise = up a 5th, +1 sharp. Each neighbour shares 6 of 7 notes.

Interval Chart

An interval is the distance between two notes, measured in semitones (half-steps). Intervals are the building blocks of all scales and chords — a major chord is just a specific stack of intervals. Learning to hear intervals by ear is one of the most powerful skills in music. Each interval has a distinct emotional quality: some are stable and consonant (like the perfect 5th), others are tense and dissonant (like the tritone).

💡 BEGINNER TIP: The best way to learn intervals is to link each one to a familiar song. The "Ear Training" column shows a classic example — hum the opening two notes of that song and you'll instantly hear that interval.

Interval	Semitones	Abbr	Example (from C)	Sound / Quality	Ear Training

Key Signature Chart

A key signature tells you which notes are sharped or flatted throughout a piece, so the composer doesn't have to write accidentals on every note. C major has none. G major has one sharp (F#). The more sharps or flats, the "further" the key is from C on the Circle of Fifths. Every major key also has a relative minor — a minor key that shares the exact same notes and key signature.

Major Key	Relative Minor	Sharps / Flats	Notes Affected

Major Pentatonic Scale Chart

The pentatonic scale is the most beginner-friendly scale for improvisation — it only uses 5 notes (the major scale with the 4th and 7th removed). Because those two notes are the "tension" notes of the major scale, the pentatonic almost always sounds right, no matter which chord is playing. It's the go-to scale for country, pop, and folk solos. The highlighted (purple) notes are the pentatonic; the gold note is the root.

💡 HOW TO USE: Pick a key your song is in, select it below, and those 5 notes are your safe zone for soloing or melody-writing. You can play any of them in any order over the chords of that key — they'll almost always sound right.

Minor Blues Scale Chart

The blues scale is the minor pentatonic with one extra note added: the ♭5, called the "blue note" (marked with *). This note creates the characteristic tension and expressiveness of blues music. It's slightly "wrong" — which is exactly what makes it so right. The blues scale is your best friend for rock, blues, jazz, and soul improvisation. Try playing it over a I–IV–V progression in any key.

💡 THE BLUE NOTE: The ♭5 (marked *) is the "wrong" note that makes the blues sound so expressive. You don't hold it — you slide through it. Lean into it, then resolve to the 5th or 4th. That tension-release is the soul of blues phrasing.

Chord Number System

The Nashville Number System describes chord progressions using numbers instead of chord names, making them key-independent. Say "1–4–5" and any musician can play that progression in any key instantly. This is how session musicians communicate on the fly. UPPERCASE = Major, lowercase = minor. Select a key below to see the number system translated into real chord names and notes.

💡 WHY THIS MATTERS: If someone says "play a 1–4–5 in G," you immediately know: G, C, D. If they say "play a 1–5–6m–4 in E," you know: E, B, C#m, A. The number system is the universal language of working musicians.

Quick Reference — Chord Qualities by Degree

Major Key

#	Roman	Quality	C Maj	Notes
1	I	Major	C	C E G
2	ii	Minor	Dm	D F A
3	iii	Minor	Em	E G B
4	IV	Major	F	F A C
5	V	Major	G	G B D
6	vi	Minor	Am	A C E
7	vii°	Dim	B°	B D F

Natural Minor Key

#	Roman	Quality	A Min	Notes
1	i	Minor	Am	A C E
2	ii°	Dim	B°	B D F
3	III	Major	C	C E G
4	iv	Minor	Dm	D F A
5	v	Minor	Em	E G B
6	VI	Major	F	F A C
7	VII	Major	G	G B D

Time Signatures & Note Values

A time signature tells you how many beats are in each measure and what type of note gets one beat. It appears as a fraction at the start of a piece of music. The top number = how many beats per measure. The bottom number = which note value = 1 beat.

💡 MOST COMMON: 4/4 (four quarter-note beats per measure) is used in the vast majority of pop, rock, blues, and country. 3/4 is waltz time — three beats per measure with a "1-2-3, 1-2-3" feel. 6/8 has a flowing, compound feel — often heard in ballads and folk music.

What the Bottom Number Means

Bottom #	Note Type	Note Name	Common Examples
2	𝅗𝅥	Half note	Cut time (2/2) — march, fast classical
4	𝅘𝅥	Quarter note	4/4, 3/4, 2/4 — most Western music
8	♪	Eighth note	6/8, 9/8, 12/8 — compound meters, ballads
16	𝅘𝅥𝅯	Sixteenth note	Rare as a meter — more common in rhythm notation

Note Value Chart — Relative Durations

Note values are relative — they depend on the tempo (speed). But their relationship to each other is always the same: a whole note lasts twice as long as a half note, which lasts twice as long as a quarter note, and so on.

Note Name	Beats (in 4/4)	Relative Value	How Many Fit in a Whole Note
Whole Note	4 beats	1	1
Half Note	2 beats	1/2	2
Quarter Note	1 beat	1/4	4
Eighth Note	½ beat	1/8	8
Sixteenth Note	¼ beat	1/16	16

Dotted Notes

A dot after a note adds half its value. So a dotted half note = 2 + 1 = 3 beats. A dotted quarter = 1 + ½ = 1½ beats. Dotted notes create the lilting, swung feel heard in compound meters like 6/8 and 12/8.

Common Time Signatures

Signature	Beats/Bar	Beat Note	Feel	Used In
4/4	4	Quarter	Strong, driving, most common	Rock, pop, blues, jazz, hip-hop
3/4	3	Quarter	Waltz — emphasizes beat 1	"My Favorite Things", waltzes, country ballads
2/4	2	Quarter	March-like, brisk	Marches, polkas, folk dances
2/2	2	Half	Cut time — feels like fast 4/4	Classical, big band, fast marches
6/8	6 (felt as 2)	Eighth	Compound duple — swinging, lilting	"House of the Rising Sun", folk, Irish jigs
9/8	9 (felt as 3)	Eighth	Compound triple — rolling feel	Some folk, blues, "Wonderful Tonight"
12/8	12 (felt as 4)	Eighth	Slow blues shuffle	Blues ballads, gospel, "Feel Like Makin' Love"
5/4	5	Quarter	Asymmetric — restless, unusual	"Take Five", "Mission Impossible" theme
7/8	7	Eighth	Odd, propulsive, surprising	Balkanese folk, Radiohead, progressive rock

Musical Alphabet

Unlike the regular alphabet with 26 letters, the musical alphabet only has 7 letters: A B C D E F G — and then it repeats. Going up in pitch, you cycle forward through the letters; going down, you go backward. Understanding this cycle is the foundation for reading music, naming notes on any instrument, and understanding scales.

💡 KEY RULE: After G comes A again — but one octave higher. The same 7 letters repeat in both directions, infinitely up and down the instrument. Sharps (#) and flats (♭) modify these letters to fill in the gaps.

The 7-Letter Cycle

Going Up (Higher Pitch)

Moving to a higher-pitched note. On piano: moving right. On guitar: moving toward higher-numbered frets, or thinner strings.

Going Down (Lower Pitch)

Moving to a lower-pitched note. On piano: moving left. On guitar: moving toward lower-numbered frets, or thicker strings.

Sharps (#) and Flats (♭)

Between most letter names, there's a half-step gap that is filled by a sharp or flat. The exceptions are E–F and B–C — these are already only a half-step apart, so there's no note in between.

💡 REMEMBER: A sharp (#) raises a note by one semitone. A flat (♭) lowers it by one. E# = F, Cb = B — these are called enharmonic equivalents.

Natural Half-Steps — No Black Key Between These

E → F

Only a half-step apart. No black key between E and F on the piano. This is why the major scale pattern has a half-step between degrees 3 and 4.

B → C

Only a half-step apart. No black key between B and C on the piano. This is why the major scale has a half-step between degrees 7 and 8 (the octave).

Chord Wheel

The Chord Wheel is a practical tool built on the Circle of Fifths. The outer ring shows all 12 major keys; the middle ring shows each key's relative minor. The inner colored wheel shows the 7 diatonic chord degrees (I–vii°) for your selected key. Use the ‹ › arrows or click any outer key to rotate.

🎵 USING THE WHEEL — MAJOR KEY

Use ‹ › to rotate to your major key (shown at top)
The inner wedges show your I–vii° chord degrees
Click any wedge to see its notes and 7th chord
I, IV, V are your three most important chords — the backbone of most songs

🎵 USING THE WHEEL — MINOR KEY

Find your minor key in the middle ring (e.g. "Am")
The outer ring key above it is your relative major — rotate to it
Now re-read the inner wheel from the vi position — that's your minor i chord
Your minor key chords: vi=i, vii°=ii°, I=III, ii=iv, iii=v, IV=VI, V=VII

💡 MINOR KEY EXAMPLE: Song is in E minor? Find "Em" in the middle ring — it aligns with G major on the outer ring. Rotate to G. Your Em minor key chords are: Em(i), F#°(ii°), G(III), Am(iv), Bm(v), C(VI), D(VII). These all appear in the G major inner wheel — you just start reading from the "vi" wedge (Em) as your home chord.

        ● Major
        ● minor
        ● dim°
      

Harmonic Minor Scale

The harmonic minor scale is the natural minor scale with one change: the 7th degree is raised by a semitone. This creates a leading tone — a note just a half-step below the root — which pulls powerfully back to the tonic. The result is the distinctive sound of classical music, flamenco, metal, and Middle Eastern music. Formula: 1 – 2 – ♭3 – 4 – 5 – ♭6 – 7 (the raised 7th is the key difference from natural minor).

💡 WHY IT MATTERS (PIANO): The raised 7th turns the v chord (minor) into a V major chord — giving you a proper dominant that resolves cleanly to the i chord. This V→i resolution is the harmonic engine of most classical and tonal music in minor keys. On piano, the raised 7th is the note one semitone below your root (e.g. in A harmonic minor: G# instead of G).

Minor Pentatonic Scale

The minor pentatonic is the single most used scale for soloing in rock, blues, and pop. It uses 5 notes from the natural minor scale — omitting the 2nd and 6th (the two most "tense" minor notes), leaving only the core expressive tones. Formula: 1 – ♭3 – 4 – 5 – ♭7. It shares the same 5 notes as its relative major pentatonic — just starting from a different root.

💡 PIANO TIP: The minor pentatonic on piano is the easiest scale for improvisation in a minor key — every note sounds good over the i, iv, and v chords. In A minor, the notes are A – C – D – E – G. Try playing these over an Am–Dm–Em progression and you can't go wrong.

🔗 RELATIONSHIP TO MAJOR PENTATONIC: The A minor pentatonic (A–C–D–E–G) uses the exact same notes as the C major pentatonic (C–D–E–G–A). They are relative — just starting from a different note. This is why guitarists and pianists switch between them freely.

Chord Inversions

An inversion is the same chord with a different note in the bass (lowest position). The chord keeps its identity — same notes, same name — but its colour, smoothness, and voice-leading change. Inversions are essential on piano for moving smoothly between chords with minimal hand movement.

🎹 WHY INVERSIONS MATTER: Instead of jumping your hand across the keyboard between chords, inversions let you keep common notes in place and move only what's needed. Going from C (C–E–G) to F (F–A–C), use F's 2nd inversion (C–F–A) — the C stays put and your hand barely moves. This is the secret to smooth, professional-sounding chord playing.

How Inversions Work

Take the lowest note and move it up an octave. Repeat to get each successive inversion. A triad (3 notes) has 3 positions; a 7th chord (4 notes) has 4.

Inversion Notation Reference

Inversion	Bass Note	Triad Figure	7th Chord Figure	Slash Notation (C)
Root Position	Root (1)	5/3	7	C
1st Inversion	3rd	6/3 (or "6")	6/5	C/E
2nd Inversion	5th	6/4	4/3	C/G
3rd Inversion	7th	— (triads only have 3)	4/2 (or "2")	C/B♭

💡 SLASH CHORDS: In modern notation, inversions are written as "slash chords" — the chord name, a slash, then the bass note. C/E means a C major chord with E in the bass (1st inversion). C/G means C major with G in the bass (2nd inversion). The figures (6/3, 6/4, etc.) come from classical figured bass notation.

Augmented Chords

An augmented chord is a major triad with the 5th raised by a semitone. Where a major chord has a perfect 5th (7 semitones), an augmented chord has an augmented 5th (8 semitones). Written as C+ or Caug. Formula: 1 – 3 – ♯5.

Sound & Character

Augmented chords sound tense, unstable, and dreamlike — neither resolved nor darkly dissonant. Because the three notes divide the octave into three equal parts (major 3rd + major 3rd + major 3rd = 12 semitones), every note of an augmented chord can act as the root. C+, E+, and G#+ all contain the same three pitches.

They are most commonly used as a passing chord — particularly between I and I6 (first inversion), or as an altered V chord (V+) that creates additional tension before resolving to I.

Augmented vs Major vs Diminished

Type	Formula	5th	C example
Major	1 – 3 – 5	Perfect (7 st)	C – E – G
Augmented	1 – 3 – ♯5	Augmented (8 st)	C – E – G#
Minor	1 – ♭3 – 5	Perfect (7 st)	C – Eb – G
Diminished	1 – ♭3 – ♭5	Diminished (6 st)	C – Eb – Gb

💡 PIANO TIP: On the piano, play a major chord then raise the top note (the 5th) by one key. That's your augmented chord. Try C–E–G, then C–E–G# — hear how it floats unresolved? Now resolve it to F major (F–A–C) — that's the classic I+ → IV motion used in gospel and soul.

Augmented Chord Reference — All Keys

Double Sharps & Double Flats

These accidentals arise naturally when spelling augmented chords and other complex harmonies correctly. They are a matter of music notation convention — keeping each letter name appearing exactly once in a scale or chord.

Double Sharp (𝄪 or ×)

Raises a note by two semitones (a whole step). Written as 𝄪 or × before the note. Sounds the same as the natural note one whole step up.

Written	Sounds Like	Context
F𝄪	G	G# harmonic minor (raised 7th = F𝄪)
C𝄪	D	B augmented chord (B–D#–F𝄪)
G𝄪	A	E aug chord spelled correctly

Why not just write G instead of F𝄪? In a chord or scale built on a G# root, the 3rd must be a B (some kind of B), and the 5th must be a D (some kind of D). Using G would violate the "one letter per degree" rule and create a written chord with two G's, making it unreadable in notation. The double sharp preserves the letter sequence.

Double Flat (𝄫 or bb)

Lowers a note by two semitones (a whole step). Written as 𝄫 or bb before the note. Sounds the same as the natural note one whole step down.

Written	Sounds Like	Context
B𝄫	A	Diminished 7th chord on C (C–Eb–Gb–B𝄫)
E𝄫	D	Db diminished chord
A𝄫	G	Bb diminished chord (Bb–Db–A𝄫)

Why not just write A instead of B𝄫? In the key of Cb major, B𝄫 is the 7th scale degree — it must be spelled as some kind of B to preserve the letter sequence B–C–D–E–F–G–A–B. Writing A would create a scale with two A's and no B, which breaks the notation system. Double flats are most common in flat-heavy keys and diminished 7th chords.

Sus, Add & Power Chords

Beyond triads and 7ths, these chord types are essential for modern music. They add colour, texture, and emotion without the full complexity of extended harmony.

Suspended Chords (Sus2 & Sus4)

A suspended chord replaces the 3rd with either the 2nd or 4th. Removing the 3rd means the chord is neither major nor minor — it sounds open and unresolved, "suspended" in the air, waiting to move. The sus4 is the most common and typically resolves down to the major chord.

Sus2 — Formula: 1 – 2 – 5

Replace the 3rd with the 2nd. Open, airy, atmospheric. Very common in pop, ambient, and new-age music.

Sus4 — Formula: 1 – 4 – 5

Replace the 3rd with the 4th. Creates tension that wants to resolve to the major chord. The 4th "wants" to step down to the 3rd.

Add Chords (Add9 & Add2)

An add chord adds a note to a triad without creating a full 7th chord. The 3rd is kept (unlike sus chords). Add9 is the most popular — it adds warmth and sophistication to a major or minor chord without the complexity of a 9th chord (which implies all intervening extensions).

Add9 — Formula: 1 – 3 – 5 – 9 (= 2 up an octave)

Lush, open, modern. The 9th adds colour without dissonance. Extremely common in pop, R&B, and neo-soul piano.

Minor Add9 — Formula: 1 – ♭3 – 5 – 9

Same as add9 but with a minor 3rd. Expressive and emotional — widely used in film scores and introspective pop.

Power Chords (5th Chords)

A power chord uses only the root and perfect 5th — no 3rd at all. Because there's no 3rd, it is neither major nor minor. This ambiguity, combined with the strength of the perfect 5th interval, gives it a powerful, neutral sound that works perfectly with distortion. Written as C5. Formula: 1 – 5 (sometimes with the octave: 1 – 5 – 8).

💡 PIANO NOTE: Power chords are most associated with electric guitar, but on piano they create a strong, open sound useful for bass-register figures, left-hand accompaniment, and minimalist arrangements. Play root + 5th in the left hand while the right hand plays melody for a clean, uncluttered texture.

Cadences

A cadence is a chord progression at the end of a musical phrase that creates a sense of rest, pause, or continuation. Cadences are the punctuation of music — some feel like a full stop, others like a comma, others like a question mark. Understanding them is essential for composing and analysing music.

💡 KEY INSIGHT: The V chord is the most harmonically tense chord in a key — it wants to move somewhere. Where it moves (or doesn't) defines the cadence type. The V→I resolution is the strongest move in tonal music, because the leading tone (7th scale degree) rises a semitone to the root, and the dominant resolves to the tonic.

The Four Main Cadences

12-Bar Blues

The 12-bar blues is the most widely used chord form in Western popular music — the structural backbone of blues, rock and roll, jazz blues, and country. It uses only three chords (I, IV, V) arranged in a specific 12-measure pattern that repeats endlessly. Once you know it, you'll recognise it in hundreds of songs.

💡 PIANO TIP: All three chords are typically played as dominant 7ths (I7, IV7, V7) — even the I and IV, which are major chords. This gives the blues its characteristic tension throughout, not just at the V chord. Try playing the 12-bar in C: C7 – F7 – C7 – C7 – F7 – F7 – C7 – C7 – G7 – F7 – C7 – G7.

Minor Blues Chart — I, IV, V Chords

For playing blues in a minor key, the I, IV, and V chords are typically minor 7th (i7 and iv7) with the V remaining dominant (V7) for the strongest resolution. The table below shows these three chords for every key, matching the standard minor blues chord chart format.

Melody Guide — Playing Over Chord Progressions

This guide explains which notes, scales, and techniques work best for playing melodies over common chord progressions on piano. Knowing what chords are playing tells you which notes are safe, which create tension, and which to avoid.

🎹 THE CORE PRINCIPLE: Every chord is built from scale tones. The notes of the chord itself are always safe. The other notes of the key scale are passing tones — use them briefly to move between chord tones. Notes outside the scale are tension tones — use them deliberately for colour, then resolve.