AP Music Theory Cheat Sheet 2026
Intervals — Number & Quality
| Half Steps | Interval Name | Quality | Example (C up) |
|---|---|---|---|
| 0 | Unison | Perfect (P1) | C–C |
| 1 | Minor 2nd | m2 | C–D♭ |
| 2 | Major 2nd | M2 | C–D |
| 3 | Minor 3rd | m3 | C–E♭ |
| 4 | Major 3rd | M3 | C–E |
| 5 | Perfect 4th | P4 | C–F |
| 6 | Augmented 4th / Diminished 5th | A4 / d5 (tritone) | C–F♯ / C–G♭ |
| 7 | Perfect 5th | P5 | C–G |
| 8 | Minor 6th | m6 | C–A♭ |
| 9 | Major 6th | M6 | C–A |
| 10 | Minor 7th | m7 | C–B♭ |
| 11 | Major 7th | M7 | C–B |
| 12 | Octave | P8 | C–C (upper) |
Inversion rule: Interval + inverted interval = 9. Perfect ↔ Perfect, Major ↔ Minor, Augmented ↔ Diminished. (M3 inverts to m6; P5 inverts to P4)
Key Signatures
Order of Sharps: F C G D A E B
Mnemonic: Father Charles Goes Down And Ends Battle
| Sharps | Major Key | Minor Key |
|---|---|---|
| 0 | C major | A minor |
| 1 (F♯) | G major | E minor |
| 2 (F♯,C♯) | D major | B minor |
| 3 | A major | F♯ minor |
| 4 | E major | C♯ minor |
| 5 | B major | G♯ minor |
| 6 | F♯ major | D♯ minor |
| 7 | C♯ major | A♯ minor |
Order of Flats: B E A D G C F
Mnemonic: Battle Ends And Down Goes Charles' Father
| Flats | Major Key | Minor Key |
|---|---|---|
| 1 (B♭) | F major | D minor |
| 2 (B♭,E♭) | B♭ major | G minor |
| 3 | E♭ major | C minor |
| 4 | A♭ major | F minor |
| 5 | D♭ major | B♭ minor |
| 6 | G♭ major | E♭ minor |
| 7 | C♭ major | A♭ minor |
Flat key shortcut: Major key = second-to-last flat. (4 flats = A♭ major; last 2 flats are G♭ and C♭, so key = A♭)
Scales & Modes
Major Scale Pattern
W – W – H – W – W – W – H (W=whole step, H=half step)
Natural Minor Scale (Aeolian)
W – H – W – W – H – W – W
Harmonic Minor
Natural minor with ♯7 — creates augmented 2nd between ♭6 and ♯7
Melodic Minor
Ascending: ♯6 and ♯7 · Descending: natural minor
The 7 Modes (white keys on C)
| Mode | Starts on | Quality |
|---|---|---|
| Ionian | C | Major (same as major scale) |
| Dorian | D | Minor ♭7 (minor with raised 6) |
| Phrygian | E | Minor ♭2 (minor with lowered 2) |
| Lydian | F | Major ♯4 (major with raised 4) |
| Mixolydian | G | Major ♭7 (major with lowered 7) |
| Aeolian | A | Natural minor |
| Locrian | B | Diminished ♭2♭5 |
Chord Qualities & Construction
| Chord | Intervals | Symbol | Example (C) |
|---|---|---|---|
| Major triad | M3 + m3 (= P5) | C | C–E–G |
| Minor triad | m3 + M3 (= P5) | Cm | C–E♭–G |
| Augmented triad | M3 + M3 (= A5) | C+ | C–E–G♯ |
| Diminished triad | m3 + m3 (= d5) | C° | C–E♭–G♭ |
| Major 7th | Major triad + M7 | Cmaj7 | C–E–G–B |
| Dominant 7th | Major triad + m7 | C7 | C–E–G–B♭ |
| Minor 7th | Minor triad + m7 | Cm7 | C–E♭–G–B♭ |
| Half-diminished 7th | Dim triad + m7 | Cø7 | C–E♭–G♭–B♭ |
| Fully diminished 7th | Dim triad + d7 | C°7 | C–E♭–G♭–B♭♭ |
Inversions
- Root position: root in bass — figured bass: 5/3 (just Roman numeral)
- First inversion: 3rd in bass — figured bass: 6/3 (just "6")
- Second inversion: 5th in bass — figured bass: 6/4
- 7th chord inversions: 7 (root), 6/5 (1st inv), 4/3 (2nd inv), 4/2 or 2 (3rd inv)
Roman Numeral Analysis
Diatonic Chords in Major
| Roman Numeral | Quality | Function |
|---|---|---|
| I | Major | Tonic (stable) |
| ii | Minor | Pre-dominant |
| iii | Minor | Tonic/mediant |
| IV | Major | Pre-dominant (subdominant) |
| V | Major | Dominant |
| V7 | Dom. 7th | Dominant (strongest drive to I) |
| vi | Minor | Tonic (relative minor) |
| vii° | Diminished | Dominant function |
Diatonic Chords in Minor
| Roman Numeral | Quality |
|---|---|
| i | Minor (tonic) |
| ii° | Diminished (pre-dominant) |
| III | Major |
| iv | Minor (pre-dominant) |
| V or V7 | Major dom. (requires raised ♯7) |
| VI | Major (subtonic) |
| vii° | Diminished (from harmonic minor) |
Cadences
| Cadence Type | Progression | Effect |
|---|---|---|
| Authentic (PAC) | V(7) → I | Root position, soprano on 1̂ — strongest resolution |
| Imperfect Authentic (IAC) | V → I | 1st inv or soprano not on 1̂ — weaker authentic |
| Half Cadence (HC) | any → V | Ends on V — like a musical question |
| Plagal (PC) | IV → I | "Amen" cadence — gentle, hymnlike |
| Deceptive (DC) | V → vi | Expected I substituted by vi — surprising |
PAC requirements: (1) V or V7 in root position; (2) I in root position; (3) soprano on tonic (scale degree 1̂). All three required for a Perfect Authentic Cadence.
Four-Part Voice Leading Rules (SATB)
Prohibited Parallels
- Parallel 5ths: Two voices move in same direction to another P5 — FORBIDDEN
- Parallel octaves: Two voices move in same direction to another P8 — FORBIDDEN
- Direct (hidden) 5ths/8ths: Outer voices move in same direction to P5 or P8 by leap in soprano — avoid
Voice Ranges (Standard SATB)
| Voice | Range |
|---|---|
| Soprano | Middle C (C4) to G5 |
| Alto | G3 to C5 |
| Tenor | C3 to G4 |
| Bass | E2 to C4 |
Doubling Rules
- Root position: double the root (preferred)
- First inversion: double the soprano note (often 3rd); avoid doubling the 3rd of dominant chords
- Second inversion (6/4): always double the 5th (the bass note)
- Leading tone (7̂): NEVER double in dominant chords — it must resolve up to tonic
- 7th chords: include all 4 notes (no doubling needed)
Resolution Rules
- Leading tone (7̂) → resolves UP to tonic (1̂)
- Chordal 7th → resolves DOWN by step
- Augmented 2nd → avoid in SATB writing (use melodic minor ascending)
- Tritone in V7 → 7̂ resolves up to 1̂; 4̂ resolves down to 3̂
Non-Chord Tones (NCTs)
| NCT | Approach | Leave |
|---|---|---|
| Passing Tone (PT) | Step | Step (same direction) |
| Neighbor Tone (NT) | Step | Step (return to same note) |
| Suspension (SUS) | Held over (same pitch) | Step DOWN (resolution) |
| Retardation (RET) | Held over | Step UP |
| Appoggiatura (APP) | Leap | Step (opposite direction) |
| Escape Tone (ET) | Step | Leap (opposite direction) |
| Anticipation (ANT) | Step or leap | Held to become chord tone |
| Pedal Point (PED) | Held or repeated | Held through multiple chords |
Most-tested suspensions: 4–3 (over V), 7–6, 9–8, and 2–3 (bass suspension). Figured bass number = interval above the bass.
Secondary Dominants & Modulation
Secondary Dominants
- V/V = dominant of the dominant (e.g., in C major: D major → G major)
- V7/IV = dominant 7th of IV (e.g., in C major: C7 → F major)
- Written as V/x or V7/x where x = target chord Roman numeral
- Any major or minor chord can be "tonicized" except vii°
Common Modulation Techniques
| Type | How it Works |
|---|---|
| Pivot chord | Chord that belongs to both old and new key — most common in AP questions |
| Direct modulation | Sudden change without a pivot chord |
| Sequential modulation | Rising or falling sequence leads to new key |
Closely Related Keys (to C major)
- G major (1 sharp), F major (1 flat)
- D major (2 sharps), B♭ major (2 flats)
- A minor (relative), D minor, E minor, G minor
Musical Form & Structure
| Form | Structure | Example Genre |
|---|---|---|
| Binary (AB) | Two sections, each often repeated | Baroque dance movements |
| Ternary (ABA) | Statement – contrasting section – return | Minuet & Trio, Scherzo |
| Rounded Binary | A | :B A': (B brings back A material) | Baroque binary that sounds like ABA |
| Rondo (ABACA...) | Recurring A theme between contrasting episodes | Classical rondos, finales |
| Sonata form | Exposition – Development – Recapitulation | Symphony 1st movements |
| Through-composed | No repeated large sections | Many art songs (Lieder) |
| Strophic | Same music repeated for each stanza | Folk songs, hymns |
Phrase Structure
- Period: Two phrases (antecedent + consequent) where antecedent ends on HC or IAC, consequent ends on PAC
- Parallel period: Both phrases begin with same material
- Contrasting period: Phrases begin differently
- Sentence: Presentation (basic idea × 2) + Continuation (fragmentation + cadence)
Rhythm, Meter & Tempo
Meter Types
- Simple: beat divides into 2 (2/4, 3/4, 4/4) — top number = beats per measure
- Compound: beat divides into 3 (6/8, 9/8, 12/8) — divide top # by 3 for beats
- Asymmetric: 5/4, 7/8, 11/8 — unequal beat groupings
Common Tempo Markings (slow → fast)
- Grave (very slow, solemn) → Largo → Lento → Adagio → Andante → Moderato → Allegretto → Allegro → Vivace → Presto → Prestissimo
Rhythmic Devices
- Syncopation: accent on normally unaccented beat or off-beat
- Hemiola: 2-against-3 or 3 beats felt as 2 (common in Baroque cadences)
- Augmentation: note values doubled (rhythm slowed)
- Diminution: note values halved (rhythm sped up)
AP Music Theory Exam Format
Section I: Multiple Choice (40%)
- ~75 questions in 80 minutes
- Part A: Written (score analysis, theory identification)
- Part B: Aural (listening to recordings, identifying elements)
Section II: Free Response (60%)
- Part A: Written (no recordings) — 65 min
- Part B: Aural (with recordings) — 40 min
- Tasks: melodic dictation, harmonic dictation, figured bass realization, melody harmonization, part writing, score analysis
Highest-weight FRQ tasks: Melodic dictation (write a melody from hearing it), part writing (add soprano, alto, tenor to a given bass), and harmonic analysis (write Roman numerals with figured bass for given passage).
More AP Music Theory Resources
Score calculator and all AP cheat sheets