Key Signatures

Determining a key from the key signature

You can determine the key of a song/piece just by looking at its key signature.

Rule for sharp: The key is one half-step up from the last sharp in the key signature. For example, if there is one sharp in the key signature (F#) you know the song is in the key of G

Rule for flat: The key is the next to last flat in the key signature.

For example is there is two flats (Bb and an Eb) in the key signature you know the song is in the key of Bb.