How do I find the key of a song?
Short answer
Find the note that sounds like home: hum the final note of the chorus or song and match it on a piano or tuner app. Then decide whether the song sounds major or minor. Confirm with the chords or a key-detection tool, because detectors can confuse related major and minor keys.
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Explanation
A key is built around a home note, the tonic, where melodies and chord progressions feel resolved. Songs very often end on the tonic chord, which is why the final note is a good first clue.
Major and minor keys can share the same notes. C major and A minor both use only white keys, so you need the home note, not just the note set, to tell them apart.
Sheet music shows the key signature at the start of each line. The number of sharps or flats narrows the key to one major and one relative minor.
| Key signature | Major key | Relative minor |
|---|---|---|
| No sharps or flats | C major | A minor |
| 1 sharp (F♯) | G major | E minor |
| 2 sharps (F♯, C♯) | D major | B minor |
| 1 flat (B♭) | F major | D minor |
| 2 flats (B♭, E♭) | B♭ major | G minor |
| 3 flats (B♭, E♭, A♭) | E♭ major | C minor |
Find the key by ear
- Play the end of the song and hum the last sustained note.
- Match that note on a piano app or a tuner to get its name.
- Decide whether the song feels major (bright) or minor (darker).
- Check that the first and last chords fit that key, or compare with a key-detection tool.
Frequently asked questions
Can an app tell me the key?
Key-detection tools give a useful estimate, but they can mix up a major key with its relative minor. Confirm by ear.
What if the key changes in the last chorus?
Many songs modulate, often up a semitone or tone. Note the key of each section you will sing.
Do I need to know the key to change it?
No. You can shift by semitones and judge by ear. MR Maker shifts a backing track from -6 to +6 semitones.
Make a backing track from your own file
Upload an audio file you are authorized to use (MP3, WAV, FLAC, M4A, AAC, OGG or MP4, up to 50MB). Conversion costs 1, 2 or 3 credits for low, medium or high quality; changing the key adds 1 credit.
Upload a songRelated guides
Sources
Each source was opened and checked on the date shown.
- Key Signatures — musictheory.net (checked )
- The Major Scale — musictheory.net (checked )
- The Minor Scales — musictheory.net (checked )
- Key (music) — Wikipedia (checked )