Yes, it appears to be the key of C# minor.

Hi Rafal, you can tell right away that it doesn’t stick to a single diatonic key because it has both a Bdim and an Fdim. If you’re using lowercase to indicate minor chords, then I think it is based in A minor. However, the shift to F#/D7 indicates that you are departing from A minor key. Dm7 would make sense for the key of A minor, but D7 has that F#. Fdim has a G#. I hope this helps!

Thanks for the question. This looks like A minor to me. It’s an intesting progression so I’m adding some additional thoughts. The sus chords take the major third out of the C chords. The Csus2/B adds the minor 7th of C back with the B so it’s not quite a C minor or Dominant 7. G add 11 adds the F which theoretically pairs well with the F chord that follows. I’d be curious to know how that sounds as Gsus4 vs G add 11 as the B seems to be a specified with the add11 notation to resolve to the C in F/A.

In any case, it is a fun progression. I hope this helped and provided a little more insight. As always, musicians can go out of key from time to time, which can make key-determination a bit of an art.

Thanks for the question. This is very close to the key of E minor (as you mentioned), which is the relative minor of G major. The exception is that the Dmaj11 has a major 7th in it (C#) instead of C. B minor does not include C# unless you’re playing a Bm9 chord. The C# would resolve nicely to the Am7 (1/2 step movement between chords). This is a case where the out-of-key note may add interest to the progression. An easy way to test this is by omitting the C#. I hope this helps.

Em7 > Dmaj11 > Am7 > Bm

It’s basically Emin with a C# note during the Dmaj11 and Bm chords, which means the progression shifts from Em to Bm each chord change. Is this correct?

Sorry for the very late reply, but it looks like the key of A minor to me.