C major
 |
|
| Relative key | A minor |
|---|---|
| Parallel key | C minor |
| Dominant key | G major |
| Subdominant | F major |
| Component pitches | |
| C, D, E, F, G, A, B, C | |
C major (or the key of C) is a major scale based on C, with the pitches C, D, E, F, G, A, and B. Its key signature has no flats and no sharps.
C major's relative minor is A minor and its parallel minor is C minor.
C major is one of the most common key signatures used in western music. Most transposing instruments playing in their home key are notated in C major; for example, a clarinet in B♭ sounding a B-flat major scale is notated as playing a C major scale. The white keys of the piano correspond to the C major scale. Among brass instruments, the contra-bass tuba is in C. A pedal harp tuned to C major has all of its pedals in the middle position.
C major is often thought of as the simplest key, because there are no sharps and no flats, and beginning piano students' first pieces are usually simple ones in this key; the first scales and arpeggios that students learn are also usually C major. However, going against this common practice, the Polish-French composer Frédéric Chopin regarded this scale as the most difficult to play with complete evenness, and he tended to give it last to his students. He regarded B major as the easiest scale to play on the piano, because the position of the black and white notes best fit the natural positions of the fingers, and so he often had students start with this scale. There are no black keys in the C major scale, thus it doesn't fit the natural positions of the fingers well.
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