Find Chord
Instantly search and identify the chord being played based on its position on the fretboard
Découvrez nos applications
Une sélection aléatoire d'applications musicales pour enrichir votre pratique
Key-based Progressions
Open a scale-driven chord-progression library: the app instantly suggests harmonic sequences that are fully diatonic or modal to the active scale. Audition, transpose, and send them straight to the progression generator or your desk in one click.
Bibliothèque de progressions
Explore hundreds of harmonic progressions spanning all 21 modes: audition, transpose, and send them straight to the progression generator with a single click.
Twelve Metronome
A full-featured metronome with a complete selection of rhythmic figures and advanced settings and functionalities
Key to chords search
Instantly determine the key of any chord progression: import the sequence or play it live, the app scans the notes, identifies the key and mode, and offers the most relevant harmonization options at a glance.
Find Scale
Search for and identify the scale that matches the notes being played
Medias
Integrated media library for your workspace: centralize, organize, and access all your YouTube, Vimeo, SoundCloud, Deezer, Spotify, Apple Music links (and more) with a single click to support and enrich your work.
Light Metronome
A straightforward, visual metronome: customize the tempo intuitively by clicking on the beat LEDs to set your perfect pulse.
Desk Layout Studio
Arrange and lay out all your pinned items—diagrams, composition scales and charts—in the Desk Editor so you can save and print your work.
Twelve-Assistant
The harmonic and music theory assistant designed for guitarists… and useful for all musicians.
Twelve-Assistant brings together everything you need to explore, understand, and play harmony — all in a single application. Search for a scale, visualize its degrees on the fretboard or the piano, hear its colors, stack chords and diagrams in a ready-to-use workspace… everything happens quickly, clearly, and without ever losing your work.
Originally designed for guitar, the tool adapts to your practice: right-handed/left-handed, 4 to 12 strings (including 7/8-string), clear high-definition SVG fingerings, and instant switching between guitar ↔ piano. Whether you’re a curious beginner, a teacher preparing a lesson, or a composer looking for ideas, Twelve-Assistant puts theory at the service of music — simply.
What you’ll love
- Explore without friction: scales, modes, and chords appear instantly with their degrees, positions, and colors.
- See & compare: compare two scales or two voicings in one click, and overlay or switch between fretboard and keyboard views.
- Build your sheets: create workspaces (chords, diagrams, notes, media in picture-in-picture), save them, duplicate them, and reopen them whenever you want.
- Stay in the flow: a dock-style bar keeps your recent apps and favorites at hand — no scattered tabs, no lost settings.
- Learn by ear: listen to each scale/chord, identify the intervals, and feel the harmonic color.
- Go further: the Harmony Core engine powers intelligent search, with analysis and creation tools that keep evolving.
For whom?
- Guitarists: visualize the fretboard, lock in your landmarks, and work on your positions and transitions.
- Pianists & producers: access the same information on the keyboard, and try out modal colors in your compositions.
- Teachers & students: prepare clear materials in just a few minutes — easy to share and reuse.
Why now?
Because a good theory tool should disappear as you use it. Twelve-Assistant lets you play, experiment, and memorize — with no pages to reload and no settings to redo. Open, explore, create — the music comes first.
Want to give it a try? Jump in, try out a few scales, build your first workspace… and see how quickly your ideas take shape.
Four years of development — why?
What are the differences between the Twelve-Assistant V1 from 2021 and the Twelve-Assistant V2 from 2025, and why did its development take four years?