Guide · Music theory
How to find the key of a song
Find the note or chord that feels like home, the one the song settles on at the end. That is usually the key. To check, write down the chords used and see which major key contains them all: if a song uses G, C, D and Em, it is in G major, or its relative minor, E minor.
Updated 20 Oct 2026
Method 1: find the home note by ear
- Listen to the end of the song. The last chord or bass note is very often the key.
- Hum along and find the note that feels finished. Match it on a piano or guitar. Call that note 1.
- Check it is major or minor. Play the major chord on that note. If it fits, it is major. If it sounds cheerful against the song, but a minor chord fits better, it is minor.
Method 2: use the chords
Write down the chords the song uses. Find the key whose chords include all of them. These are the chords in the common keys:
| Major key | Chords in it (I ii iii IV V vi) | Relative minor |
|---|---|---|
| C | C Dm Em F G Am | A minor |
| G | G Am Bm C D Em | E minor |
| D | D Em F#m G A Bm | B minor |
| A | A Bm C#m D E F#m | F# minor |
| E | E F#m G#m A B C#m | C# minor |
| F | F Gm Am Bb C Dm | D minor |
| Bb | Bb Cm Dm Eb F Gm | G minor |
Most songs use mainly I, IV and V (and often vi). If the chords are G, C, D and Em, it matches G major.
Major or relative minor?
Every major key shares its chords with a minor key: C major and A minor, G major and E minor, and so on. To tell which, look at where the song rests. If it settles on C, it is C major. If it settles on Am, it is A minor, even though the chords are the same as C major.
Method 3: read it from a chart
A chart or lead sheet usually states the key at the top. On sheet music, the number of sharps or flats at the start (the key signature) points to the key, and the last chord confirms it. If you only have the chords, use method 2.
Use an app, with care
Apps that listen and guess the key can be right, but they struggle with busy mixes and with songs that change key. Check the result against your ear and the chord table.
Write the key down
Once you know it, note it with the recording. In songdrafts the key is a field on the song, so every take of the song sits next to the key you found. You set the key yourself, and songdrafts does not detect it from the sound of the recording.
Common questions
How do I find the key of a song on guitar?
Find the note that feels like home and check which chords fit. If the chords are G, C and D, it is probably G major. A capo changes the sounding key, so use the capo chart if you play with one.
How do I find the key of a song from the chords?
Write the chords down and match them to the chord table above. The major key whose chords include all of them is the key, or its relative minor.
Does the first chord tell you the key?
Often, but not always. The last chord is usually a better clue.
What if the song changes key?
Find the key of each section separately. A change often happens before the last chorus.
How do I tell major from minor?
Listen to where the song feels finished. If it rests on a major chord it is major; on a minor chord, minor.
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