Key Signatures Chart — All 15 Major & Minor Keys

The five-second version

A song lives in a key. A key is a family of 7 notes that sound right together. Most keys aren't just the plain white-piano notes — they need a few sharps or flats to sound "in tune" with themselves.

Instead of writing ♯ or ♭ next to every single note, the composer writes them once, at the start of the line. From then on, every note on those lines or spaces is silently sharp or flat for the whole piece.

One example: G major needs F♯. So the key signature is a single ♯ parked on the F line. Every F you see in the rest of the music — high, low, anywhere — is automatically F♯.

That's it. The whole point is to save you from drowning in accidentals.

Why bother memorising them?

Three honest reasons:

• You read faster. When you see "two sharps," you instantly think "D major (or B minor)" instead of squinting at every note.
• You know the note pool. The sharps/flats tell you exactly which 7 notes belong in the song — golden info for soloing, harmonising, or transposing to a singer's range.
• You stop guessing in jam sessions. Someone says "let's do it in E♭" — now you know which notes are in and which are out.

How to read one (left to right)

1. Look right after the clef. Sharps and flats sitting there are the key signature. (Accidentals that pop up later in the music are temporary — they only last the bar they're in.)
2. Count them. Note whether they're sharp or flat. Three sharps? Four flats? Each card above shows you exactly what that looks like on both clefs.
3. Apply them everywhere. Every note on a marked line or space gets that sharp or flat — every octave, every page, until a new key signature shows up.

The sharps and flats follow a fixed order

This is the single most useful thing to know. Sharps and flats are never written randomly — they always come in the same sequence:

• Sharps: F♯ · C♯ · G♯ · D♯ · A♯ · E♯ · B♯
  • Mnemonic: Father Charles Goes Down And Ends Battle
• Flats: B♭ · E♭ · A♭ · D♭ · G♭ · C♭ · F♭
  • Mnemonic: Battle Ends And Down Goes Charles' Father (the same sentence, backwards)

So a key signature with 3 sharps is always F♯, C♯, G♯ — in that order, in those exact spots on the staff. Four sharps adds D♯. Five adds A♯. And so on. Once you know the sequence, you stop having to "read" the symbols — you just count them.

Two cheat codes for naming the key

You don't need to memorise all 15 — there's a trick for each type:

• 🎯 Sharp keys — look at the last sharp in the signature, then go up one letter. Example: 2 sharps end on C♯ → up one letter is D → D major.
• 🎯 Flat keys — the second-to-last flat is the key. Example: 4 flats (B♭, E♭, A♭, D♭) → second-to-last is A♭ → A♭ major. (One exception: a single flat = F major. Just memorise that one.)

That covers 14 of the 15 keys with no extra memorisation.

"Wait, why does every key signature have two names?"

Because every key signature is shared by a major key and a minor key. They use the exact same 7 notes — just resolving to a different "home" note.

Signature	Major key	Minor key
No sharps or flats	C major	A minor
1 sharp	G major	E minor
2 flats	B♭ major	G minor

It's like two songs sharing a wardrobe. C major sounds bright and resolved, A minor sounds darker and unresolved — but they're built from the same 7 notes. Each card above tells you both names.

How to actually use this chart

• Reading sheet music? Count the symbols → match a card → you've got the key.
• Picking a key to play in? Browse a card, look at the note pool, then jump to its diatonic chords (the 7 chords that naturally live in the key — each one links to the Chord Finder so you can see how to play it).
• Learning theory? Pair this with the Circle of Fifths to see how keys relate to each other, and the Guitar Scale Finder to play those notes on the neck.

Don't drown trying to memorise all 15. Start with the keys you actually play — usually C, G, D, A, E, F. Get those reflexes solid first. Once those click, the rest fall into place automatically, because they all follow the same order.