Key signatures

About 2 min to read, then 10 practice questions

Written once, at the start

G major: F sharp, on the top line

G major in the bass clef

Writing a sharp before every F in G major would be tiring. So the sharps or flats a key needs are written once, at the start of every stave, as a key signature. They count for every note with that letter name, in every octave, all through the piece.

Quick check

What is the note marked x?

The four keys

Learn these by heart

C major

Sharps

G major

D major

Flats

F major

One sharp means G major. Two sharps mean D major. One flat means F major. A key signature with nothing in it means C major.

Quick check

This key signature has two sharps. Which major key is it?

A scale with a key signature

F major with its key signature: the B needs no flat of its own

A scale can be written with its key signature instead. Then the sharps or flats are not written again by the notes. So exam scales come with or without a key signature.

Remember

A key signature: the sharps or flats, once at the start of every stave.
C none. G F sharp. D F sharp and C sharp. F B flat.
It counts for every note with that letter, all through the piece.

Practise this: 10 questions, about 8 min

Answering from memory soon after reading is what makes it stick, so now is a good time.

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