Free tool
Audio Speed Changer
Speed up a lecture or slow down a phrase for transcription. Adjust playback from 0.5× to 2×, then download WAV or Opus.
Drop the audio you want to speed up or slow down
MP3, WAV, OGG, M4A · no file uploads
Pitch changes with speed here, like tape playback. See the explanation below.
Waveform and playback
,Engine: the browser's native Web Audio API, without external libraries. Audio stays on your device.
Edit audio without uploading your file
Choose a file your browser can decode, preview the result, then download WAV or the compressed format offered by your browser. WAV export is uncompressed; compressed export may run in real time. Format support depends on the browser and source codec. Keep the original file and listen to the exported result before using it.
Does speed adjustment preserve pitch?
No. Playback-rate changes also change pitch. Use a dedicated time-stretching editor if you need to change tempo while keeping the original pitch.