How to Find the Key of a Song (4 Methods + Chord Table)

To find the key of a song, find its home note (the tonic) and decide whether the song sounds major or minor around it. Hear the tonic by ear, work it out from the chords or read the key signature. For a quick answer from audio, use the song key finder; the methods below show how to check it.

Which method should you use?

Pick a method by what you have

You have	Best method	Typical time	Watch out for
An audio file or a link to play	Song key finder, then an ear check	Seconds	Major/relative-minor mix-ups, key changes
Only your ears (no instrument)	Method 1: hum the tonic, match it on a piano app	2–5 minutes	Humming the 5th instead of the tonic
A chord sheet or tabs	Method 3: chord table	1 minute	Borrowed chords, capo shapes
Sheet music	Method 4: key signature + minor check	30 seconds	Relative minor has the same signature

Method 1: hum the tonic by ear

The tonic is the note that feels like rest. Melodies circle away from it and come back at the ends of phrases, and it usually sounds right held under the whole song.

1. Play the chorus and hum one long note that fits under it. Change it until it never clashes.
2. Check it at the end of phrases: the melody should land on or near it.
3. Find that note on a piano, a guitar or a free piano or tuner app. If you have no instrument, sing it into the vocal range test, which shows the note name you are holding.
4. Test major or minor: play a major chord on the note, then a minor one. The chord that blends with the song gives the mode: G + major chord fits = G major.

The common slip is humming the 5th (the dominant) instead of the tonic. The 5th also fits most chords but feels slightly unfinished; try the note 7 semitones below it (a fifth down) and see which feels like home.

Method 2: listen to the last chord and the bass

Most songs end on the tonic chord, so the final chord is a strong clue: a song that ends on E minor is probably in E minor. The bass note under the last chord is even more reliable than the melody, which may end on the 3rd or 5th.

Treat it as a clue, not proof. Songs that fade out never reach the final chord, some end on the IV or V chord to sound open, and many songs begin on a different chord. Check what you find with method 3.

Method 3: work out the key from the chords

Each major key has seven chords built from its scale: three major (I, IV, V), three minor (ii, iii, vi) and one diminished (vii°). List every chord in the song, then find the row that contains them all:

The 7 chords of every major key (the relative minor uses the same chords, starting on vi)

Key	I	ii	iii	IV	V	vi	vii°
C major	C	Dm	Em	F	G	Am	Bdim
G major	G	Am	Bm	C	D	Em	F♯dim
D major	D	Em	F♯m	G	A	Bm	C♯dim
A major	A	Bm	C♯m	D	E	F♯m	G♯dim
E major	E	F♯m	G♯m	A	B	C♯m	D♯dim
B major	B	C♯m	D♯m	E	F♯	G♯m	A♯dim
F♯ major	F♯	G♯m	A♯m	B	C♯	D♯m	E♯dim
D♭ major	D♭	E♭m	Fm	G♭	A♭	B♭m	Cdim
A♭ major	A♭	B♭m	Cm	D♭	E♭	Fm	Gdim
E♭ major	E♭	Fm	Gm	A♭	B♭	Cm	Ddim
B♭ major	B♭	Cm	Dm	E♭	F	Gm	Adim
F major	F	Gm	Am	B♭	C	Dm	Edim

The relative minor uses the same seven chords, with vi as its home chord: A minor = the C major row, starting on Am. Seventh chords count as their triad (G7 = G). In a minor key the V chord is often major, E instead of Em in A minor, so one “wrong” major chord is a clue to the minor key.

Worked examples

Chord lists matched to keys (example progressions, not specific songs)

Chords in the song	Rows that contain them	Deciding clue	Key
G, D, Em, C	G major (E minor)	The chorus resolves to G	G major
E, A, B7, C♯m	E major (C♯ minor)	B7 is the V7 of E; it pulls to E	E major
Dm, B♭, C, A7	None exactly: F major holds Dm, B♭, C	A7 is the major V of D minor (raised C♯)	D minor
Am, F, C, G	C major (A minor)	Which chord feels like home: C or Am?	C major or A minor (use the check below)

Every example, and every row of the table, is also a group of neighbours on the circle of fifths: a key’s I, IV and V chords sit side by side.

Method 4: read the key signature on sheet music

Count the sharps or flats at the start of the staff. With sharps, the key is a half step above the last sharp; with flats, it is the second-to-last flat (one flat = F major). The signature gives two answers, a major key and its relative minor. To choose, look for the raised 7th of the minor key written as an accidental in the music:

All 15 key signatures, both keys each, and the accidental that points to the minor

Key signature	Major key	Relative minor	Minor-key clue (raised 7th)
No sharps or flats	C major	A minor	G♯
1 sharp	G major	E minor	D♯
2 sharps	D major	B minor	A♯
3 sharps	A major	F♯ minor	E♯
4 sharps	E major	C♯ minor	B♯
5 sharps	B major	G♯ minor	F double sharp
6 sharps	F♯ major	D♯ minor	C double sharp
7 sharps	C♯ major	A♯ minor	G double sharp
1 flat	F major	D minor	C♯
2 flats	B♭ major	G minor	F♯
3 flats	E♭ major	C minor	B
4 flats	A♭ major	F minor	E
5 flats	D♭ major	B♭ minor	A
6 flats	G♭ major	E♭ minor	D
7 flats	C♭ major	A♭ minor	G

Example: one sharp and frequent D♯ accidentals point to E minor, not G major. The music key chart shows each signature on the staff.

Major or relative minor? The final check

Every method above can land on the right notes but the wrong home, because C major and A minor (and every relative pair) share all seven notes. Run these checks, in order:

1. Home chord: loop the chorus and stop it on each candidate chord. The one that sounds finished is the tonic.
2. First and last bass notes: they point to the tonic more often than not.
3. Raised 7th: a G♯ or an E major chord in a song with no sharps points to A minor.
4. Mood is a weak clue: a sad song can be major, so do not decide on mood alone.

The distinction also matters for what comes next: turning a song from major to minor is a different job from changing its key, and the major to minor converter handles both the relative and the parallel minor.

When the answer is still unclear

• The song changes key. A final chorus a semitone or two higher is common; find the key of each section separately.
• The recording is not at standard pitch. Bands that tune down a half step, or old recordings, sit between keys. In our tests, one recording of Pachelbel’s Canon (written in D major) played a semitone low and read as D♭ major (how we test).
• The song is modal. A loop of D, C and G that keeps landing on D is D Mixolydian: it uses the notes of G major but D is home.
• A capo hides the key. Chord shapes of G with a capo on fret 2 sound in A. Add one semitone per fret, or count with the semitone calculator.

After you know the key

If the song sits wrong for your voice, find a better key in what key should I sing in and shift a recording with the online key changer (how to change the key of a song). For chords and sheet music, transpose music online rewrites them in the new key, and how to transpose a song explains the steps. The theory behind tonic, scale and mode is in what is a song key.

Frequently asked questions about finding the key

What is the easiest way to find the key of a song?

Upload the audio to a key finder, then confirm by humming the tonic over the chorus. By hand, the last chord plus the chord table above is usually quickest.

Can I find the key of a song without an instrument?

Yes. Hum the home note, then match it with a piano app, a tuner app or our vocal range test, which names the note you sing.

Does the first chord of a song tell you the key?

Often, not always. Many songs start on the IV or vi chord. The last chord and the chord that feels like home are more reliable.

How do I find the key from chords only?

List all the chords, find the row of the chord table that contains them, then decide between that major key and its relative minor with the home-chord check.

What key has no sharps or flats?

C major and its relative minor, A minor. A frequent G♯ or E major chord points to A minor.

Why does a key finder say C major when the song is in A minor?

Both keys use the same notes, so detectors weigh which note sounds most central and can pick the relative key. Run the final check above. More guides are in our pitch and key guides, every tool is on all pitch tools, and the online pitch changer is on the home page.