Change an audio file's speed online
Speed up or slow down an audio file (0.5x to 2x) without changing its pitch, directly in your browser.
or click to select it
Speed up or slow down an audio file (0.5x to 2x) without making it sound higher- or lower-pitched, directly in your browser. Unlike just playing a file faster in a regular player, the pitch stays natural here.
Uses a time-stretching algorithm that changes the audio's duration while keeping the original pitch. That's different from simply playing a file faster, which also raises the pitch and produces that characteristic 'chipmunk' effect.
Use cases
- Listen to podcasts or recorded lectures faster to save time.
- Slow down a song or recording to transcribe it or learn an instrument by ear.
- Adjust an audio file's duration to fit a video or presentation.
How it works
- 1
Upload your audio
Supports MP3, WAV, M4A, FLAC, AAC, OGG and OPUS.
- 2
Choose the speed
From 0.5x (slower) to 2x (faster).
- 3
Download the MP3
With the new speed applied.
Technical details
Relies on ffmpeg.wasm's atempo filter, which reprocesses the audio samples to preserve the perceived pitch while changing playback speed.
Frequently asked questions
Does it change the pitch of the voice?
No — the algorithm keeps the original pitch, unlike simply speeding up playback, which does alter it.
Is there a speed limit?
The available range is 0.5x to 2x, enough for the vast majority of uses without noticeable sound artifacts.