Music Chord Candidate Analyzer
For each short interval of recorded audio, this page groups spectral peaks into twelve pitch classes and compares them with 24 major and minor triad templates. It shows the three closest candidates, pitch-class evidence and the gap between the first two scores. A quiet interval, isolated note or ambiguous mix remains unclassified. Key, instrumentation, drums, modulation, seventh chords and dense polyphony can all change the outcome. Template fit is an internal relative score, not a probability of a correct transcription.
Key features
- Analyze up to 30 seconds of locally decoded WAV or another browser-supported audio format.
- Choose half-second or one-second intervals and see major/minor candidates, uncertainty or silence.
- Inspect all twelve pitch-class contributions and the gap between the two top template fits.
- Load an audible C–Am–D example to check the method before analyzing your own file.
- Export the full timed result as CSV or JSON including settings and pitch-class data.
How to use
- Select a local audio file or load the included C–Am–D example.
- Choose interval length and mono mix, left or right input channel.
- Analyze, then choose an interval on the timeline to inspect candidates, fits and pitch evidence.
- Listen to uncertain intervals yourself and download CSV or JSON for further review.
Use cases
- Inspect changing chord candidates in a short, clear practice recording.
- Review how the candidate timeline responds to an example that changes key center.
- Use pitch-class clues before writing or checking a chord chart by ear.
Frequently asked questions
Does this produce an accurate chord chart or score?
No. It supplies signal-based candidates for 24 major/minor triads only. It does not fully interpret seventh chords, inversions, bass, instrument harmonics, drums, vocals or harmonic context. Confirm by ear.
Is a fit score of 90 a 90% chance of correctness?
No. The 0–100 fit is an uncalibrated internal measure of how detected pitch classes match a chord template, not a probability. Also inspect the competing candidate, gap and chroma.
Why is an audible interval marked uncertain?
If three chord tones are not independently supported, the sound is weak, or two templates fit similarly, the tool avoids forcing a label. A lone note or chord boundary can be uncertain.
Which files are supported?
WAV, MP3, Ogg and other audio that the current browser AudioContext can decode, up to 12MB and 0.5–30 seconds, 8–96kHz, mono or stereo. A filename extension cannot guarantee codec support.
Is my audio uploaded?
No. Decoding, FFT, candidate ranking and playback happen in the browser tab. CSV and JSON are created locally only when you request an export.
Privacy
Audio and analysis results remain in browser memory and are not uploaded to an application server. Temporary data is lost when you close the tab.
Comments & questions