Hi
For those who don't know how to work out a key from the key signature:
If the key signature contains sharps, the key is a semi-tone above the last sharp.
For example, if the key signature is 3 sharps (which would be F#, C# and G#), the key is one semi-tone above the G#; the key of A.

If we're talking about flats, the key is the second-last of the flats, (except that if it's one flat, with B flattened, the key is F). But for all the others, the second-last is the key.
So if you see 4 flats (Bb Eb Ab Db) the key is Ab.

Bear in mind that this applies to major keys. A minor key 3 semi-tones below the major key has the same signature.
So in the above examples, the key of A major and F# minor would both be 3 sharps; Abmajor and Fminor would both have the key signature of 2 flats.

How to tell if a song is in a major or minor key is not a simple process, but usually the chord on which the main melody finishes will give the key.

Hope this helps

Regards
Mike Laatz
www.capetownjazz.com

Mike Laatz
Cape Town