Key Signature Calculator
Calculate the key signature for any major or minor key. See which sharps or flats are in the key signature.
C Major Key Signature
No sharps or flats
How to Use This Calculator
- Select the key you want to find the signature for (C, D, E, etc.).
- Choose whether it\'s a major or minor key.
- The calculator displays the key signature showing which sharps or flats are in that key.
- Use this to understand key signatures, read sheet music, or learn music theory.
Key Signature Theory
Key signatures follow the circle of fifths pattern:
Flat keys (counterclockwise): F(1b), Bb(2b), Eb(3b), Ab(4b), Db(5b), Gb(6b), Cb(7b)
Order of sharps: F-C-G-D-A-E-B
Order of flats: B-E-A-D-G-C-F
Example: G major has 1 sharp (F#). D major has 2 sharps (F#, C#). F major has 1 flat (Bb).
Full Description
Key signatures are essential for reading and writing music. They indicate which notes are consistently sharped or flatted throughout a piece, eliminating the need to write accidentals for every occurrence. A key signature appears at the beginning of each staff and applies to all notes of that letter name throughout the piece (unless cancelled by an accidental).
Key signatures follow the circle of fifths, a pattern that shows the relationship between keys. Moving clockwise around the circle adds sharps, while moving counterclockwise adds flats. The order of sharps is always F-C-G-D-A-E-B, and the order of flats is the reverse: B-E-A-D-G-C-F. This pattern makes it easy to determine key signatures once you understand the system.
This calculator helps you find the key signature for any major or minor key. Select the key and mode, and it shows which sharps or flats are in that key signature. Use it to learn music theory, understand sheet music, or determine the key of a piece. Understanding key signatures is fundamental to reading and writing music.
Frequently Asked Questions
What is a key signature?
A key signature is a set of sharps or flats at the beginning of a musical staff that indicates which notes are consistently raised or lowered throughout the piece. It tells you what key the music is in without having to write accidentals for every note.
How do I determine the key signature?
Key signatures follow the circle of fifths. Moving clockwise adds sharps (G=1#, D=2#, A=3#, etc.). Moving counterclockwise adds flats (F=1b, Bb=2b, Eb=3b, etc.). The order of sharps is F-C-G-D-A-E-B. The order of flats is B-E-A-D-G-C-F.
What's the difference between major and minor key signatures?
Major and minor keys with the same key signature are called relative keys. For example, C major and A minor both have no sharps or flats. The relative minor is always 3 semitones below the major key. The key signature is the same, but the tonal center (tonic) is different.
How do I read key signatures?
For sharps: The last sharp is the leading tone (7th scale degree) of the major key. For flats: The second-to-last flat is the major key name. For example, if the last sharp is F#, the key is G major. If the flats are Bb and Eb, the key is Bb major.