Choose a key from the approved list, enter the scale yourself, build the triads, explore extended chords, then plan a 4-chord progression. Use Check buttons to verify your working.
1) Choose your key
Scale degrees
Correct scale
Diatonic triads
2) Your scale (type the 7 or 8 notes)
Circle of Fifths
3) Build the diatonic triads (type the 3 notes for each)
Write each chord as three note names (comma-separated). Order doesn’t matter; enharmonics are treated as distinct spellings (Db ≠ C#).
Degree
Quality
Your chord notes
Check
4) Extended chord options
5) Plan your 4-chord progression
6) Mood-based suggestions
Chord Progression Rules (PRSHS)
Major key movement
I can appear anywhere in a progression.
ii → I, V, vii°
iii → I, ii, IV, vi
IV → I, ii, iii, V, vii°
V → I, vi
vi → I, ii, iii, IV, V
vii° → I, iii
Minor key movement (natural minor)
i can appear anywhere in a progression.
ii° (or ii) → i, iii, V, v, vii° or VII
III (or III+) → i, iv, IV, VI, #vii° or vii°
iv (or IV) → i, V, v, vii° or VII
V (or v) → i or VI
VI (or #vii°) → many (e.g. i, III, III+, iv, IV, V, v, vii°, VII)
vii° (or VII) → i
Answers
Use only if you’re stuck. This reveals the scale & diatonic triads for the selected key.
Teacher Notes
Students must enter scale and triads; checks validate against the selected key.
Enharmonics are treated as distinct spellings: Eb ≠ D#.
Extended chords show diatonic 7ths plus simple add6/add9 suggestions.
Colour: screen turns purple only after “Answers revealed”.