Auto-detects (or lets you set) the current key, works out the semitone distance to your target key, and pitch-shifts the file to match — handy for matching a backing track to a singer's range or another song's key.
The Key Transposer shifts a song into a different key without changing its speed. It first detects the key of your recording (with a Camelot code for DJs), then lets you move it by semitones or straight to a target tonic.
Typical uses: bring a karaoke backing track into your vocal range, match two tracks for a harmonic mix, or transpose a loop to your project’s key.
Key detection uses a chroma analysis: the file’s spectrum is folded into 12 pitch classes with a tuning correction (so a recording slightly off A=440 is still read correctly) and correlated with the Krumhansl–Schmuckler major and minor key profiles. Transposition is then a pitch shift by the shortest interval between the detected tonic and your target, performed with resampling plus WSOLA to keep the duration.
Shift the backing track a few semitones up or down.
Make two tracks harmonically compatible.
Match sampled loops to the song key.
Play along in an easier key.
| Detection | Chroma + Krumhansl–Schmuckler with tuning correction |
|---|---|
| Transpose | −12…+12 semitones or to any tonic |
| Duration | Unchanged |
Best on tonal music with a clear key; spoken word has no key.
Use the Pitch Changer for cents-level control.
It always picks the shorter path around the 12-note circle — for example C to F# shifts up 6 semitones rather than down 6, since both are equally short; other pairs have one clearly shorter direction, which it uses automatically.
It uses the same Key Finder analysis available elsewhere on the site, which works best on tonally clear material — see the Key Finder page for its known limitations, or just set the key manually if you already know it.
This tool runs entirely in your browser using the Web Audio API. Nothing is uploaded, stored or shared — there is no server to send your file to, so it works offline once the page has loaded.
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