Find the chord progression of any song from audio. Open an MP3, WAV or M4A file, or let this free chord progression finder listen through your microphone while the song or your guitar plays. It shows every chord in time, the main progression in Roman numerals, the key and the guitar shapes. Already know the chord names? Type them into the chord progression analyzer instead.
Chord Progression Finder
Find the chords of a song from an audio file, or live while it plays. The audio never leaves your device.
Nothing is uploaded or recorded: the music is analysed in your browser.
Next
Home chord (I)Tonic family (vi, iii)Build-up (IV, ii)Tension (V, vii°)◆ Outside the key? = uncertain
Chord progression
Play it your way
Chords in this song
Tap a chord to hear it. Most-used chords first.
Chord sheet (text)
Related Tools
- Song Key Finder
Only need the key of a song? Get the key, Camelot code and scale.
- Pitch Shifter
Change the key of the audio itself, up or down in semitones.
- Scale Finder
Find which scales fit the notes of a riff or a solo.
- BPM Detector
Measure the exact tempo of the same song.
- Guitar Tuner
Tune up before you play along with the chords.
- Interval Ear Training
Train your ear to hear chord changes yourself.
How to Find the Chord Progression of a Song
- Add the music. Choose a song file or drop it on the box (MP3, WAV, M4A, OGG or FLAC, up to 80 MB and 20 minutes). No file? Press Listen live and play the song from another device, or play it on guitar or piano. Try a demo song shows how it works.
- Wait a few seconds. A 4-minute song takes about 3 seconds on a laptop and a little longer on a phone, all on your own device.
- Press play and follow along. The current chord is shown big with its guitar shape, the next chords count down beside it, and the chord lane scrolls with the music. Tap any chord in the lane to jump there.
- Read the progression. The summary shows the loop the song uses most, for example I – V – vi – IV: C G Am F, with the key, tempo and a capo tip.
- Make it playable. Transpose the chords, switch to simple chords, pick guitar or piano shapes, then copy or download the chord sheet.
Chord Finder From Audio or Live Through the Microphone
A song file gives the best result: the finder hears the whole track, so it can smooth the chord timeline, find the key and play the song back in sync with the chords. Use it for MP3s you own, voice memos of your band or a recording of your own playing.
The microphone mode is a live chord finder: play a song from a speaker, a video or a streaming app nearby, or strum along yourself, and the current chord appears within about half a second. When you press Stop and show the progression, the finder analyses everything it heard and gives you the same full timeline and summary as for a file. Nothing is recorded or uploaded in either mode.
What the Chord Progression Finder Shows
| Result | What it tells you |
|---|---|
| Chord timeline | Every chord change with its time, colour-coded by its role in the key; tap a chord to hear the song from there |
| Now and next | The chord playing right now, its Roman numeral and guitar or piano shape, and the next three chords with a countdown |
| Chord progression | The loop the song repeats most (up to 8 chords), in chord names and Roman numerals, and how many times it plays |
| Chord types | Major, minor, 7, maj7, m7, diminished, augmented, sus2, sus4 and power chords; slash chords such as G/B when the bass plays another chord note |
| Key, tempo, tuning | The key of the song, its tempo in BPM when the beat is clear, and whether it is tuned to A4 = 440 Hz |
| Capo tip | The capo fret that turns the song into easy open shapes, for example capo 3 to play E♭ B♭ Cm A♭ as C G Am F |
| Transpose and simple chords | Move all chords up or down to suit your voice, or reduce 7ths and sus chords to plain major and minor |
| Chord sheet | A text sheet with the key, the progression and the chords with times, to copy or download |
Reading the Result: Roman Numerals and Common Progressions
Roman numerals name each chord by its step in the key, so the same progression looks the same in every key: upper case for major chords, lower case for minor, ° for diminished. In C major, C G Am F is I – V – vi – IV; in D major the same pattern is D A Bm G. The chord lane colours follow the same idea: violet for the home chord and its relatives, blue for chords that build up (IV, ii), navy for chords that pull back home (V), and amber with a ◆ for chords from outside the key.
| Progression | Example | Heard in |
|---|---|---|
| I – V – vi – IV | C G Am F · D A Bm G | Countless pop hits |
| vi – IV – I – V | Am F C G | The same loop started on the minor chord |
| I7 – IV7 – V7 | A7 D7 E7 | 12-bar blues |
| ii7 – V7 – Imaj7 | Dm7 G7 Cmaj7 | Jazz standards |
| i – VI – iv – V | Am F Dm E | Minor songs with a major V chord |
Why the key matters: Am F C G fits both A minor and C major. The finder chooses the chord the song keeps returning to, especially at the start and the end, and shows the numerals for that key.
How the Chord Detection Works
The finder turns the audio into a chromagram: every 46 milliseconds a Fourier transform measures the notes in the sound, the overtones of lower notes are removed, and the result is folded into the 12 pitch classes C to B, with a separate bass chroma for the lowest notes. The tuning of the recording is measured first, so a track at A4 = 432 Hz or a slightly sharp guitar is read correctly. Each slice is compared with 120 chord templates (12 roots × 10 chord types) plus “no chord”, and a hidden Markov model with the Viterbi algorithm finds the most likely chord sequence, first on its own, then again with a key-aware prior that favours the chords of the detected key. The bass decides between inversions and slash chords.
We tested it with 15 synthesised songs with known chords: piano, strummed guitar, electric piano and synth pads, with and without drums, at 90–128 BPM, one tuned 35 cents sharp and two with a sung melody, reverb and background noise. The right chord (root and major/minor) was shown 98% of the time on average, 91–94% for the hardest mix, and the main progression was correct in all 15 songs. Drum loops and noise correctly gave “no chords”. How we test our tools is described on our methodology page.
Tips for Better Results
- Pick a part with guitar, piano or keyboard. A drum solo or a spoken intro has no chords to find.
- In microphone mode, keep the phone or laptop close to the speaker and turn the music up; a quiet room helps.
- If a chord is marked with ? or looks odd, tap it in the lane and listen: fast passing chords and busy vocals can hide the harmony for a moment.
- Use Simple chords when you just want to strum along: Cmaj7 becomes C and Dsus4 becomes D.
- To pick out a melody or a riff note by note rather than the chords, use the note finder.
Frequently Asked Questions
Is my song uploaded anywhere?
No. The file is decoded and analysed by your own browser, and microphone sound is analysed live and never recorded. Nothing is sent to a server.
Can I find the chords of a song on YouTube or Spotify?
Yes: play it on one device and press Listen live on another, or on the same laptop near its speakers. You can also open any song file you own.
What does N.C. mean?
N.C. means “no chord”: silence, drums alone or a single melody line with no harmony under it.
Why does it show G/B instead of G?
The part after the slash is the bass note. G/B is a G chord with B in the bass, which makes a smooth bass line such as C – G/B – Am. Switch on Simple chords to hide the bass notes.
Can I type chord names instead of using audio?
Yes: the chord progression analyzer linked at the top takes typed chords and returns the key, Roman numerals and secondary dominants. To train your own ear to hear chord changes, see the ear training guide.
Is it as accurate as a human musician?
For clear pop, rock, folk and blues recordings it gets most chords right, but dense jazz voicings, heavy distortion and fast changes are harder. Treat the timeline as a strong first draft, check doubtful chords by ear, and use the pitch detector to check a single note.