Pitch Shifter Online: Change a Song's Key
Open a song saved on your phone or computer and shift its key in semitones without touching the tempo, or slow it down without changing the pitch. Use it to bring a backing track down to your vocal range, to play along with a recording that isn't tuned to A 440 and to learn a solo by ear.
How to use it
- Tap Choose song or drag the file in (MP3, M4A, WAV, OGG or FLAC). On iPhone, the audio has to be in the Files app.
- Press play and use the − and + buttons under Key: each tap is one semitone (a half step). Fine tune, in cents, fixes a recording that is slightly off pitch.
- To practice, drop the Speed to 75% or 50%; the pitch stays the same.
- Set A and B (or drag your finger across the waveform) to loop a section.
- Download WAV renders the file in the key and speed you chose; if your browser supports it, a smaller format (AAC or OGG) shows up too.
Help and explanations
Everything runs in your browser and the file never goes to any server. YouTube links won't work: use an audio file from your device.
How many semitones to shift
A half step is 1 semitone and a whole step is 2. To move a backing track from G to F, go down 2; from E to C, go down 4. When the song has a clear key, it appears under the control along with the new key. Not sure which key suits your voice? Find your range with the vocal range test and compare it with the lowest and highest notes of the melody.
Up to 3 or 4 semitones the sound stays natural. From 6 on, the singer on the recording starts to sound odd; the Preserve vocal timbre (formants) option helps when the track has vocals.
Slow it down to learn songs by ear
Between 50% and 75% you can hear every note of a solo or a strumming pattern without the pitch changing, and the A–B loop repeats the passage until your fingers get it. Check the notes with the online tuner and the tempo with the metronome.
Tips
- Karaoke or backing track in your key: go down 1 or 2 semitones if the chorus feels strained; go up if the song sits too low and sounds muddy.
- Playing along and everything sounds slightly out of tune? The recording may not be at A 440: nudge the fine tune until the chords lock in.
- To learn a song for band practice, start at 90% and work your way up to 100%.
- Just need the key and the BPM? Use the song key and BPM finder.
Frequently asked questions
How do I change the key of a song online for free?
Open the file here, adjust the Key and download. It's free, with no sign-up and no watermark.
How do I lower a song by a whole step?
Go down 2 semitones: a whole step is 2 semitones and a half step is 1. The text under the control shows the math and, when it can, the new key (G major → F major).
Can I change the pitch of a song from YouTube?
No. The page doesn't download audio from the internet; it only opens files on your device, like a backing track you bought or recorded.
How do I slow down a song without changing the pitch?
Use the Speed control, from 50% to 150%. Pitch and speed are independent.
Does it work on a phone?
Yes, in Chrome and Firefox on Android and in recent Safari on iPhone. On iPhone, save the audio to the Files app first.
Why is the download a WAV and not an MP3?
Browsers don't ship with an MP3 encoder. The WAV is lossless; when your browser has an encoder, an AAC or OGG button appears too, and those files are much smaller.
Is my file uploaded to a server?
No. Everything happens in your browser, using the open-source Signalsmith Stretch library. For files longer than 15 minutes, only the beginning is processed (8 minutes on phones).