About Guitar Theory Studio
Built by a solo developer and gigging guitarist: how one theory engine draws every diagram, spells every note and keeps the site and the app in agreement.
Who makes it
Hi, I’m Brad — a solo developer and a gigging guitarist. Guitar Theory Studio is where my love of guitar and my love of code met: one theory engine that draws everything, so the neck, the chords, and the practice loop can never disagree with each other.
It is an independent project, with no ads and no data selling. If something is wrong or missing, tell me at support@guitartheorystudio.com.
How the diagrams are made
Nothing on this site is drawn by hand. Every scale, mode, chord shape, arpeggio and position comes out of one music-theory engine — the same code that runs the app.
The engine works from intervals and the real geometry of the neck: six strings, standard tuning or the alternate tuning you choose in the app, and true fret spacing. These reference pages are generated from it, so the A minor pentatonic on a page and the A minor pentatonic in the app are the same shape, note for note — as are the chords of G major and every other diagram here.
How notes are spelled
A seven-note scale uses each letter name once. That is why the 3rd of E major is written G# rather than Ab, and the 4th of F major is Bb rather than A#. Pentatonic and blues scales skip letters, so their chords are spelled from the key they come from.
Where a key would need double sharps or double flats, the pages use its everyday name instead: D# Locrian rather than Eb Locrian. Chords are named from the same spelling, so a chord chart and the scale it came from always agree.
How it is checked
Every fact on a reference page — the notes, the intervals, the chords in a key, where each position sits — is computed by the engine, not typed in.
The written explanations are built around those computed facts, and the ten questions in the Daily come from the same engine. One engine keeps the site and the app consistent with each other; it does not make them right by itself. What it does mean is that a mistake lives in one place, and fixing it there fixes it everywhere it shows up. Spotted one? support@guitartheorystudio.com.
Free, with a trainer on top
Every tool works in the browser with no account and no card: the fretboard, chords, arpeggios, the practice loop, the Daily and every reference page.
GTS Pro is the optional trainer: workouts built from what you miss and a practice plan that adapts week to week. Pricing · For guitar teachers · Learn guitar theory
Find out what you should learn next. Five questions and Guitar Theory Studio builds you a four-week plan through the fretboard, chords, scales, arpeggios and ear training — week one free.
Build my free plan →