Key signatures at a glance
The order of sharps and flats, quick rules for naming the key, and what it means for your hands.
Key points
- Sharps: F C G D A E B. Flats: the reverse.
- Major key with sharps: a semitone above the last sharp.
- With flats: the second-to-last flat names the key.
A key signature tells you which notes are sharp or flat for the whole piece. Missing it is one of the most common sight-reading errors, so make checking it a habit.
The order
Sharps always appear in this order: F♯ C♯ G♯ D♯ A♯ E♯ B♯. Flats are the reverse: B♭ E♭ A♭ D♭ G♭ C♭ F♭. A phrase like "Father Charles Goes Down And Ends Battle" (and the reverse for flats) helps some people.
Naming the major key
- Sharps: the key is one semitone above the last sharp. Last sharp C♯ → D major.
- Flats: the key is the second-to-last flat. Flats B♭ E♭ A♭ → E♭ major. One flat alone is F major.
- Each major key shares its signature with a relative minor three semitones lower (G major / E minor). Check the last bass note and look for a raised 7th (D♯ in E minor) to tell them apart.
Common keys for early reading
| Signature | Major | Relative minor |
|---|---|---|
| none | C | A minor |
| 1♯ (F♯) | G | E minor |
| 2♯ (F♯ C♯) | D | B minor |
| 1♭ (B♭) | F | D minor |
| 2♭ (B♭ E♭) | B♭ | G minor |
| 3♭ (B♭ E♭ A♭) | E♭ | C minor |
Turn it into hand shape
Before you play, put your hand on the keyboard and touch the black keys the key signature asks for. In G major your hand "knows" F♯ is the black key; that physical reminder works better than remembering it mentally mid-phrase. Also watch for accidentals, which last only until the end of the bar.
