Chords and scales: which scale to use over each chord on ukulele

On the ukulele in G–C–E–A with a reentrant high G, the fourth string is a high note — the physical order of the strings doesn't match the order of pitches. That changes everything in the chord–scale relationship: what looks low on the diagram can sound high to the ear.

Reference shapes

The instrument's four open strings: the starting point for hearing each scale degree against a stable chord.

The same open notes as C6 under another name — practical proof that context names the chord.

One finger turns the open strings into a maj7; on the first string, D, F and F# reveal 9, 11 and #11 in the voice everyone hears.

The second degree of C in a compact position, ideal for practicing Dorian in campanella on the way to G7.

The most comfortable dominant on the neck: clear third and seventh in the high layer, no bass needed.

Reentrancy: the map is not the territory

In reentrant tuning, the fourth string (G) sounds higher than the third (C). That means the diagram lies about register: inversions and bass notes indicated in the chart have to be checked by the actual sound, string by string. In return, reentrancy gifts the instrument natural campanella — neighboring scale degrees fall on different strings and overlap like bells, an effect that elsewhere demands elaborate fingering and here happens almost by itself.

A free chord in the open strings

Strum all four open strings: G–C–E–A is already a ready-made chord — C6, which can also be read as Am7, in other words the same set of notes with two names depending on context. This is the instrument's best laboratory for the topic: let the open strings ring and walk the C major scale up the first string, hearing each degree rub against or settle into the chord.

Role in the arrangement and styles

In vocal accompaniment, in pop, folk and Hawaiian music, the ukulele occupies the high layer and leaves the low end to others — or to no one, and that's fine. In chord melody, the melody lives in the shape's highest voice, and the scale choice is heard exactly there: over Cmaj7, alternate D, F and F# on the first string to hear 9, 11 and #11 changing the arrangement's character. Scale lines descend less than the pattern suggests — reentrancy hands back a high note where you expected a low one.

Common mistakes on the ukulele

Trusting the diagram for inversions and slash chords: with the fourth string high, the visual bass is rarely the sounding bass.
Transferring fingerings memorized in other contexts without checking the actual pitch of each note.
Forcing bass lines the register doesn't offer, instead of owning the high layer as home territory.
Ignoring campanella: fingering the whole scale on a single string wastes the tuning's greatest advantage.

Does the reentrant G get in the way of studying scales?

It confuses at first and becomes an advantage soon after. The high fourth string places neighboring degrees on different strings, letting scale notes ring over one another — campanella. The adjustment needed is aural: name the actual pitch of each note instead of trusting the visual position.

How do I know which is the lowest note of my chord?

Play the shape string by string, from the fourth to the first, and listen: in reentrant tuning, the lowest is usually the third string (C), not the fourth. Knowing where the real low note sits keeps you from misreading your own chord when choosing the scale.

When you're ready to go from reading to playing, the Chord & Fret app puts this fretboard interactive in your hand — grab it on the stores.

See the full theory: Chords and scales: which scale to use over each chord →

References

Content reviewed against the standard harmony literature — verified bibliography below.

John King — The Classical Ukulele (Flea Market Music, 2004)
James Hill — The Ukulele Way (6 vols.)
Tony Mizen — The Romantic Ukulele
Carlos Almada — Harmonia Funcional (Editora da Unicamp, 2009; 2ª ed. 2012)
Bohumil Med — Teoria da Música (Musimed)

Updated July 9, 2026