Music Theory  ·  Harmony  ·  Composition  ·  Collaboration

Every scale.
Every chord.
Every relation.

A comprehensive music theory toolkit for composers, arrangers, musicians, and producers. Explore scales, chords, Neo-Riemannian voice leading, build progressions, and connect with other music makers through Collabo — a live browser-based collaboration room with video chat, audio chat, turn-based track building, MIDI export, and WAV export.

Scale Encyclopedia Chord Finder Neo-Riemannian
Live Collaboration
Collabo
browser DAW

Collabo gives music producers a fast way to meet, talk, and create without leaving the browser. Use built-in video and audio chat to swap ideas, take turns arranging drums and melodies, build a shared loop in real time, then export the finished collaboration as MIDI or WAV for your DAW.

Launch Collabo →
🎹 Piano roll 🥁 Drum sequencer 📹 Video + audio chat 🎲 Random pairing ⬇ MIDI & WAV export

Built for beatmakers, composers, and remote collaborators who want quick creative sessions: discover new producers, sketch musical ideas together, communicate face-to-face, and bring the exported files back into Ableton, Logic, FL Studio, Reaper, or any MIDI/WAV-friendly setup.

Sequencer preview
Drum grid + piano roll · Turn-based editing · Real-time sync over WebRTC
Theory tools
Reference
Scale Encyclopedia
45 scales across every category with chord degrees, Roman numeral analysis, piano diagrams, guitar voicings with inversions, and scale relationships.
45 ScalesAll 12 KeysChord DegreesGuitar VoicingsPiano Diagram
Chord Progression Builder
Chord & Scale Finder
Build chord progressions with quarter, half, and whole note durations and export to MIDI or PDF lead sheet. Enter notes via piano, note grid, or interactive guitar fretboard — with 8 tunings, capo, and custom tuning support.
Progression BuilderFretboard Input8 Tunings + CapoMIDI ExportLead Sheet PDF50+ Chord Types
Advanced Theory
Neo-Riemannian Explorer
Navigate harmonic space through the Tonnetz, Cube Dance, and Circle of Fifths. Apply P, R, L, N, S, H transformations and find compatible scales for any chord set.
TonnetzCube DanceCircle of FifthsP/R/L Transforms
Composition
Chord Substitutions
Reharmonisation reference covering tritone substitutions, secondary dominants, borrowed chords, chromatic mediants, and extended/altered chords with audio in any key.
Tritone SubBorrowed ChordsSecondary DominantsAll 12 Keys
Topics covered

Diatonic Harmony

Major, natural minor, all seven modes, diatonic chord functions and Roman numeral analysis.

Jazz Scales

Melodic minor, harmonic minor, Lydian dominant, Super Locrian/Altered, all bebop scales, diminished.

Exotic & World Scales

Hungarian minor, Byzantine, Phrygian dominant, Persian, Hirajoshi, In, Iwato, Egyptian, Neapolitan.

Symmetrical Scales

Whole tone, diminished HW & WH, augmented hexatonic, tritone scale, Prometheus/Mystic scale.

Neo-Riemannian Theory

P, R, L, N, S, H triadic transformations. Hexatonic cycles. Tonnetz geometry. Cube Dance.

Chord Substitutions

Tritone sub, backdoor dominant, diatonic substitution, secondary dominants, chromatic mediants.

Guitar & Fretboard

Interactive fretboard with 8 tunings, custom tuning, capo. Chord voicings and inversions.

Notation & Export

Export progressions to MIDI, PDF chord charts with slash notation, and lead sheets with tab.

Scale library sample
ScaleCategoryFormulaCharacter
Major (Ionian)Diatonic1 2 3 4 5 6 7Bright, stable — the foundation of Western harmony
DorianModes1 2 b3 4 5 6 b7Minor but hopeful — jazz, blues, funk staple
Lydian DominantJazz1 2 3 #4 5 6 b7Floating, sophisticated — unresolved dominant 7ths
Super Locrian (Altered)Jazz1 b2 #2 3 b5 b6 b7Maximum tension — every note altered, Parker hallmark
Phrygian DominantWorld1 b2 3 4 5 b6 b7Flamenco, Middle Eastern, dramatic
Hungarian MinorWorld1 2 b3 #4 5 b6 7Eastern European character — two augmented 2nds
HirajoshiWorld1 2 b3 5 b6Japanese koto — serene, meditative pentatonic
Whole ToneSymmetrical1 2 3 #4 #5 b7All augmented chords, no tonal gravity
Bebop DominantBebop1 2 3 4 5 6 b7 7Chord tones on downbeats — the bebop language
Prometheus (Mystic)Hexatonic1 2 3 #4 6 b7Scriabin's Mystic Scale — hauntingly unresolved
View all 45 scales →