Theory Warrior explains music theory from first principles — the twelve notes, the intervals between them, the scales and keys they form, and the chords and progressions built on top. The premise of the site is that theory is not a rulebook but a description: names for things your ear already does. So every page leads with what a thing is and why it works, in plain language, with the exact notes on the table — and no instrument, notation, or prior training assumed.
How the site is organized
Three layers. The reference sections — notes, intervals, scales, modes, keys, chords, and progressions — document the material exhaustively: every interval, every scale type in every key, all sixty-two chord qualities on all twelve roots. The harmony guides are the connective essays: functional harmony, cadences, voice leading, borrowed chords, secondary dominants, and the rest of how chords actually behave in songs. And the tools put the same data to work — transposing charts, naming intervals, finding scales. Start anywhere; everything cross-links.
Part of the Warrior Network
Theory Warrior is the instrument-neutral hub of the Warrior Network — the "what it is and why it works" home, alongside sister sites that show the same ideas on real instruments. Concept pages here door out to String Warrior, the network's reference for chords, scales, and practice tools on more than twenty string instruments; a chord you study here can be seen, voiced, and played there.
Accuracy
Every table on the site is generated from one shared, tested data layer — the same formulas the network's instrument sites use to voice chords and scales — and the harmony guides' worked examples are verified against that layer in continuous integration, so a diatonic table or chord spelling in an essay can never drift from the data underneath it. Pages state only what the data supports: interval formulas, note spellings, key tables, and curated, widely-taught reference examples. When something is an alias or a convention rather than a law, the page says so.