At a glance
- Cost
- 100% free, no account
- Finds the key
- Automatically, from all 24 major and minor keys
- Transpose by
- Up to an octave either way, plus cents
- Speed
- Stays the same unless you choose otherwise
- Singers
- Formant protection for natural vocals
- Saves
- MP3 or WAV
Transposing a song
- Open the song. Within a second or two, its detected key appears, for example "G major".
- Choose a destination. Select a key from the list, which picks the smallest shift, or step up and down in semitones. Octave buttons are there too.
- Fine-tune if necessary in cents, to match an instrument that isn't at concert pitch.
- Render and download. Leave Keep original tempo and Natural-sounding vocals on for the most realistic result.
When to change a song's key
Fit your voice
Drop a song two or three semitones if the chorus is out of reach, or raise it to brighten a low melody.
Match an instrument
Brass and woodwind players often need recordings in B♭ or E♭. Guitarists in drop or half-step tunings can match their setup.
Mix in key
DJs and producers transpose tracks so they sit in the same or a neighbouring key and blend without clashes.
Fix tuning
Old tapes and vinyl rips often drift sharp or flat. A few cents of correction brings them back to A = 440 Hz.
How it works
Key detection. The tool measures how strongly each of the 12 pitch classes appears across the song, known as a chroma profile. It compares that profile against reference profiles for all 24 major and minor keys (the Krumhansl–Schmuckler method). The best match is shown along with the runner-up, which is often the relative major or minor that shares the same notes.
Pitch shifting. The transposition itself uses Signalsmith Stretch, a polyphonic pitch-shifting engine that moves every frequency component to its new pitch while holding timing steady. With formant preservation enabled, the vocal resonances stay where they were, so a lowered voice doesn't turn into a giant and a raised one doesn't become a cartoon.
Semitone cheat-sheet
| Move | Example | Sounds like |
|---|---|---|
| ±1 semitone | A → B♭ | A subtle lift or drop |
| ±3 semitones | A → C | Noticeably higher or lower, still natural |
| ±5 semitones | A → D | A different voice range |
| ±12 semitones | A → A | A full octave |
Shifts within ±4 semitones sound the most transparent. Pair the tool with the Vocal Remover to build karaoke tracks in exactly your key.
Common questions
Does changing the key change the speed?
Not by default. With Keep original tempo on, the song keeps its exact length. Turn it off if you want pitch and speed to change together.
Can it turn a major song into a minor one?
No. Transposing moves every note by the same amount, so the mode stays the same. Changing major to minor would require rewriting individual notes.
What if the detected key is wrong?
Songs that modulate, or that are mostly percussion, can confuse the detector. Check the alternative suggestion, or simply shift by semitones manually.
Is the key changer free and private?
Yes. It's free, and both key detection and pitch shifting run entirely in your browser.