What is a key?
A key is a home note, called the tonic, together with the scale built on it. In the key of G major the tonic is G and the notes are G A B C D E F♯. Songs in a key mostly use those notes and the chords built from them, and the music feels settled when it comes to rest on the tonic.
What each key page tells you
- The key signature (how many sharps or flats) and every note of the key.
- The chords in the key, as triads and seventh chords, with their Roman numerals and links to guitar shapes.
- Popular chord progressions in that key, with piano fingering.
- The relative and neighbouring keys, and the best capo position for guitar.
Not sure which key you are in? Enter your chords in the chords to key finder. To see all the key signatures together, use the key signature chart.
Frequently asked questions
What is a musical key?
A key is a home note (the tonic) plus the scale built on it. Most of a song's notes and chords come from its key, which is why the key tells you which chords will sound right together.
How many keys are there?
There are 12 different pitches to start a key on, each with a major and a minor version, giving 24 keys. Seven of them can be written two ways (F♯ or G♭, for example), so you will meet up to 30 key names.
How do I find the key of a song?
Look at the chords: the key is the scale that contains all of them, and the first and last chords usually name the tonic. The chords to key finder works it out for you.