Sharps and Flats: Key Signatures

Every major key has a unique combination of sharps or flats called its key signature. Music based on a major scale is in a major key, while music based on a minor scale is in a minor key. The key signature tells you which notes are consistently sharp or flat.

Order of Sharps

Sharps always appear in the same order (ascending fifths):

F♯ – C♯ – G♯ – D♯ – A♯ – E♯ – B♯

Order of Flats

Flats also appear in a fixed order (ascending fourths):

B♭ – E♭ – A♭ – D♭ – G♭ – C♭ – F♭

Notice that both sequences contain the same letter names—the flat order is simply the reverse of the sharp order.

The Circle of Fifths

The Circle of Fifths organizes all major keys by their key signatures.
• Clockwise = keys gain sharps.
• Counterclockwise = keys gain flats.
• C Major is the only key with no sharps or flats.

Clockwise keys: G–D–A–E–B–F♯–C♯
Counterclockwise keys: F–B♭–E♭–A♭–D♭–G♭–C♭

Traditional Method

Locate the key on the Circle of Fifths, count the number of steps from C, then apply the sharps or flats in their fixed order.

Example: A Major is three steps clockwise from C, so it has 3 sharps: F♯, C♯, G♯.
A Major = A–B–C♯–D–E–F♯–G♯

The NANDI Method

Watch the companion YouTube lesson below to learn how to identify key signatures directly from the fretboard.

Instead of memorizing the Circle of Fifths, the NANDI Method derives key signatures using the interval pattern of fourths already found on the guitar.

Finding Sharps

Rule: Drop one half-step (one fret) from the root, then count upward in fourths until you reach B. Every note before B is sharp.

Example: A Major
A → G♯ → C♯ → F♯ → B
Sharps = G♯, C♯, F♯
A Major = A–B–C♯–D–E–F♯–G♯

Notice that the sharps stop when you arrive at B.

Finding Flats

The fourth pattern naturally begins on F:

F → B♭ → E♭ → A♭ → D♭ → G♭ → C♭ → F♭

Each new key simply adds the next fourth.

Examples
• F Major → B♭
• B♭ Major → B♭ E♭
• E♭ Major → B♭ E♭ A♭
• A♭ Major → B♭ E♭ A♭ D♭

Example: A♭ Major

A♭ – B♭ – C – D♭ – E♭ – F – G

Because counting in fourths forms the foundation of the NANDI Method, you already know the order of flats. Beginning on F, simply continue moving in fourths:

F → B♭ → E♭ → A♭ → D♭ → G♭ → C♭ → F♭

Each additional fourth adds one more flat to the key signature.

Watch the companion video below to learn a simple shortcut for identifying flats in every key. 

Major Keys Across the Fretboard

The diagrams below show the notes of the G, D, A, and E major scales arranged horizontally across all six strings. Notice how the sharp notes appear in the same fourth order learned with the NANDI Method.

Traditional theory memorizes key signatures from the Circle of Fifths. The NANDI Method derives them directly from the fretboard using the interval pattern of fourths. Once the fourth pattern is understood, identifying sharps and flats becomes a logical process rather than an exercise in memorization.