Speed up or slow down any audio file (0.25× to 4×) without the chipmunk effect, or transpose the pitch by up to ±12 semitones while the tempo stays put. FFmpeg WebAssembly processes everything on your device — great for podcasts, lectures, transcription, and instrument practice.
How to use Audio Speed & Pitch Changer
Drop in an audio file (MP3, WAV, M4A, OGG, FLAC…).
Pick Speed (with optional tape-style mode) or Pitch, and set the amount with the slider or presets.
Click the action button, compare the result with the original, and download it as MP3 or WAV.
Frequently asked questions
Will speeding up the audio make voices sound like chipmunks?
No — by default the tempo changes while the pitch is preserved (FFmpeg’s atempo filter). If you want the classic tape effect where pitch follows speed, enable "Tape-style".
Can I change the pitch without changing the speed?
Yes — Pitch mode transposes by semitones (±12, i.e. one octave) while compensating the tempo, so the length stays exactly the same.
What speeds are supported?
0.25× (quarter speed) up to 4× — fine steps of 0.05 plus quick presets like 0.75×, 1.25×, 1.5×, and 2×.
Is my audio uploaded anywhere?
No — FFmpeg runs as WebAssembly in your browser, so the file never leaves your device.