Audio speed changer and pitch shifter
Change a recording's speed and/or pitch, together or independently — upload a file and download the result.
semitones
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Buy us a coffeeHow to use the audio speed changer
- Upload an audio file (MP3, WAV, or any format your browser can play), up to 6 minutes long.
- The file is never sent to any server — everything runs in your browser, so the progress bar shows the file being read on your own device, not an internet upload.
- Speed and pitch are independent by default: slow it down without the voice getting deeper, or raise the pitch without speeding it up. Turn on “Link pitch and speed” if you prefer the classic tape/turntable effect, where both change together.
- Press “Process” — it runs in the background, so you can keep using the page meanwhile (the tab no longer freezes on longer files).
- The “Play” button turns into “Stop” while it's playing — one button for both actions.
- Great for transcribing solos by ear, studying fast passages, adapting a song to a different vocal range, or reviewing a recording in more detail.