How this key signature quiz works
A key signature appears on a treble or bass staff — no note, no context, just the sharps or flats at the front of the line. Pick the major key from four choices; the answer always shows the relative minor too, because the signature alone can't tell you which of the two it is. Ten per round, three levels: everyday keys first, all fifteen — enharmonics included — at the top.
Read the signature, don't count it
Counting sharps every time is a tourist move. Readers know the signatures the way you know faces: two flats is B♭ major, four sharps is E major. The trick that gets you there is the same one this drill forces — see the pattern whole, answer fast, let the reveal (and the tonic chord you'll hear) correct you until the glance is enough.
Put it back into reading
Signatures matter because they set what every line and space means for the rest of the piece. Pair this with the note reading trainer to name what you see, the rhythm trainer to place it in time, and the full guide to reading sheet music for the method that ties it together.