Key Signature Finder
Pick a major or minor key and see exactly which notes are sharpened or flattened in its key signature.
About this tool
Every major key has a relative minor that shares exactly the same key signature (e.g. C major and A minor both have no sharps or flats) — switching between Major and Minor keeps the same signature for a relative pair.
Sharps are always written in the same order, F♯ C♯ G♯ D♯ A♯ E♯ B♯ (“Father Charles Goes Down And Ends Battle”), and flats in the reverse order, B♭ E♭ A♭ D♭ G♭ C♭ F♭. The staff shows exactly where each one sits in the treble and bass clefs. Quick tricks: in a sharp key, the major key is one semitone above the last sharp (last sharp C♯, so D major); in a flat key, the second-to-last flat names the key (B♭ E♭ A♭, so E♭ major). Keys such as F♯ and G♭ major sound identical but are written differently; the tool shows the alternative.