Lesson 28 · All 12 keys

Sus4 Chord Trainer

Learn how a sus4 chord is built one semitone-count at a time — a plain fifth with the 3rd replaced by a perfect 4th, the mirror image of the sus2 chord in Lesson 27 — then put it to work with three MIDI exercises: playing all 12 sus4 chords around the circle of fourths, and 5 jazz plus 5 gospel chord progressions that show off its taut, leaning color, in every key.

How a sus4 chord is built

A sus4 chord is a 3-note chord — the same plain fifth every triad is built on, but with the 3rd swapped out for a perfect 4th instead, a half step above where the major 3rd would sit. Every sus4 chord — in any of the 12 keys — is built the exact same way, by counting semitones to the right from a root note:

  1. Start on the root — the note that names the chord.
  2. Count 5 semitones to the right to land on the perfect 4th (this replaces the 3rd entirely).
  3. From there, count 2 more semitones to the right (7 semitones from the root) to land on the perfect 5th.
Example — D sus4 (Dsus4): start on D, count 5 semitones right to reach G, then 2 more to reach A. D‑G‑A is the Dsus4 chord. The pattern 5, 2 (7 semitones total from root to top) is what makes a chord a "sus4 chord" — every one of the 12 sus4 chords is this same shape, just moved to start on a different key.
The suspended 4th creates a taut "leaning" tension that classically resolves down a step into the 3rd of a plain triad (sus4 → triad) — a staple move in gospel, rock, and pop cadences, where a Vsus4 hangs in the air for a beat before finally releasing into V. Watch out for one mix-up: a sus4 chord is not the same shape as a sus2 chord built a 4th lower, even though they can share the same three pitch classes (e.g. Csus4 = C‑F‑G, which is the same notes as an Fsus2 = F‑G‑C) — which chord it is depends on which note is the root.

Try it: pick a root and build the chord step by step

Step 1 of 3
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Chord toneNoteSemitones from rootMIDI #

All 12 sus4 chords at a glance

ChordRoot+5 semitones → 4th+2 semitones → 5th

This MIDI exercise plays all 12 sus4 chords, one after another, moving around the circle of fourths — each chord's root sits a perfect 4th (5 semitones) above the last one: C → F → B♭ → E♭ → A♭ → D♭ → G♭/F♯ → B → E → A → D → G → back to C. Every chord is played as a full 3-note sus4 chord (root, 4th, and 5th together).

Chord 1 of 12
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The 12 chords, in circle-of-fourths order

#ChordRoot4th5th

Five jazz chord progressions built around the sus4 chord — mostly using it as a taut, leaning substitute for V or IV that wants to resolve down a step. Pick a progression and play it in one key or cycle through all 12.

Key of C
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Progression in C

DegreeChordNotes

Five gospel chord progressions built around the sus4 chord — mostly using it as a taut, leaning substitute for V or IV that wants to resolve down a step. Pick a progression and play it in one key or cycle through all 12.

Key of C
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Progression in C

DegreeChordNotes