How the chord finder works
It first finds the tempo and key, then splits the track into two-beat slices. For each slice it measures the strength of the 12 notes and picks the major or minor chord whose notes fit best, with a small preference for chords that belong to the song’s key. Neighbouring slices with the same chord are merged, and the most repeated sequence is shown as the loop.
Reading the Roman numerals
The small label under each chord says where it sits in the key. In a major key, I is home, IV and V are the strong supporting chords, and vi (the relative minor) is the sad one. In a minor key, i is home, with VI, III and VII as the common companions. Many hit songs are built from just four of these in a loop, so seeing the numerals makes the pattern obvious.
| Loop | In C major | Typical feel |
|---|---|---|
| vi – IV – I – V | Am – F – C – G | emotional, anthemic |
| I – V – vi – IV | C – G – Am – F | bright, pop |
| i – VI – III – VII | Am – F – C – G (in A minor) | dark but uplifting, trap and R&B |
What it can and cannot do
- It shows major and minor triads. Sevenths, ninths, suspended and slash chords are heard as their nearest triad, so check by ear if a chord feels richer than shown.
- It works best on harmonic parts. Drum-and-808 beats with a sparse melody give fewer clear chords.
- Chord timing is placed on a two-beat grid, so quick changes inside a bar are merged.
Using chords with your vocal
Aim long notes at the chord tones (the root, third and fifth), let passing words sit on other notes of the scale, and end phrases on a chord tone. Pair this with the key finder to set your autotune to the right scale.
Like this? Let Tunedzy do the fixing.
These tools tell you what is going on. Tunedzy acts on it: it cleans, tunes to your beat’s key, fits the flow, matches an artist’s style and masters the result on your own PC. Free.
Frequently asked questions
Is the chord finder accurate?
It is a good starting point for the main progression, not a transcription. It is strongest on clear chordal music and weakest on busy, distorted or very sparse tracks. The loop is usually right even when a single chord is off.
Why does it not show 7th chords?
It reports plain major and minor triads to stay reliable. A Cmaj7 will usually show as C, and an Am7 as Am.
Does it work on a vocal-only file?
A solo vocal has only one note at a time, so there is little harmony to read. Use the beat or the full song.
Is my audio uploaded anywhere?
No. It is analysed entirely in your browser.
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