Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top.
F#6 is F#, A#, C# and D# — F# with a major sixth added on top.
It sounds warm, and finished without being sweet. It closes a tune as firmly as the triad does but without the maj7’s shine, which is why so many standards end on one.

| F# | A# | C# | D# |
|---|---|---|---|
| 1 | 3 | 5 | 6 |
Tonic — an ending chord.
Also written F#maj6, F#M6 or F# major 6. The same chord either way; which spelling you meet depends on who wrote the chart.
Root, third and seventh. The third and seventh, the guide tones, are what make the chord major, minor or dominant, so the fifth can go: it says nothing the symbol needs.
Three notes means a spare string, which is the real point. Put a tension on it.
F#6 has 6 of them, on the bottom three strings, the low-middle three, strings 6-4-3 and strings 5-3-2, from open position up to the 13th — all in one inversion, so the bass note never moves. The one to learn first is the F# shape at the nut, which is the easiest grip here.
Start with 2x132x — no barre and down at the nut. None of the shapes for F#6 uses an open string, so every one of them is movable; the lowest sits at the 1st fret. 4 of the 10 need a barre. Together they cover the neck from the 1st fret to the 15th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| 2x132x | 1st fret | F#, root position | C# | all fretted |
| 2x4342 | 2nd fret | F#, root position | F# | all fretted |
| 24x342 | 2nd fret | F#, root position | F# | all fretted |
| xx4646 | 4th fret | F#, root position | A# | all fretted |
| x9887x | 7th fret | F#, root position | F# | all fretted |
| x-9-11-11-11-11 | 9th fret | F#, root position | D# | barred |
| x-13-11-11-11-11 | 11th fret | A#, 1st inversion | D# | barred |
| 14-13-13-11-11-11 | 11th fret | F#, root position | D# | barred |
| 11-13-11-11-14-11 | 11th fret | D#, 6th in the bass | D# | barred |
| 14-x-13-15-14-x | 13th fret | F#, root position | C# | all fretted |
The same notes rebuilt from scratch give 13 drop 2 and 9 drop 3 voicings, each on its own page.
Tensions. A shell of F#6, root, third and seventh, leaves a string free, and the tones that belong over it are the 9 (G#) and the #11 (B#).
How you get to it. The turn that lands on F#6 is G#m7 to C#7 — the ii and the V of F# — and C#7 shares its third and seventh with G#m7, so the hand barely moves between them.
In which keys. Every note of F#6 belongs to C# major (the IV), Eb minor (the ♭III), F# major (the I), Ab minor (the ♭VII), Bb minor (the ♭VI) and B major (the V).
Every note of F#6 is in F# major pentatonic, F# major, F# lydian, F# mixolydian and F# lydian dominant.
Change one note of F#6 and you have F# (drop the sixth), F#maj7 (the sixth becomes a major seventh), F#m6 (the major third becomes a minor third), F#add9 (the sixth becomes a ninth), F#69 (add the ninth) or F#7 (the sixth becomes a flat seventh).
F#6 is a major chord — root, major third, fifth. Major chords on every root.
On F#6’s sound and use this page follows Mark Levine, The Jazz Piano Book (Sher Music, 1989). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.