Change Audio Speed Online

Change audio speed online for free, directly in your browser. Upload an MP3, WAV, M4A, OGG or almost any audio file, then pick a playback speed from 0.5x to 2x to speed up or slow down the track. The tool uses ffmpeg.wasm and its atempo filter to retime your audio without changing the pitch, then saves the result as an MP3. Everything happens locally on your device, so your audio is never uploaded to any server. It is a fast, private way to make podcasts, music, voice memos or lectures play faster or slower.

🔒 100% private — files never leave your device

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How to use

  1. Drop an audio file (MP3, WAV, M4A, OGG and more) into the box or click to select one from your device.
  2. Choose a playback speed: 0.5x, 0.75x, 1.25x, 1.5x or 2x.
  3. Click Apply and the tool retimes the audio in your browser without altering the pitch.
  4. Download the new MP3 file, saved with the speed factor added to its name.

Frequently asked questions

What audio formats can I speed up or slow down?

You can load almost any common audio format, including MP3, WAV, M4A, AAC, OGG and FLAC. Whatever you upload, the retimed result is always saved as an MP3 file.

Is my audio uploaded to a server?

No. The entire process runs 100% in your browser using ffmpeg.wasm. Your audio file never leaves your device and nothing is uploaded, so it stays completely private.

Does changing the speed also change the pitch?

No. The tool uses ffmpeg's atempo filter, which retimes the audio while keeping the original pitch, so voices and music sound natural at every speed instead of chipmunk-like or deep.

What speeds are available?

You can choose from five fixed options: 0.5x, 0.75x, 1.25x, 1.5x and 2x. 0.5x and 0.75x slow the audio down, while 1.25x, 1.5x and 2x speed it up.

Why does it take a moment the first time?

On first use the tool downloads a roughly 30 MB audio engine (ffmpeg.wasm). This happens only once; after that it is cached and works offline, so future conversions start much faster.

Is there a file size limit?

There is no hard limit set by the tool, but because processing runs entirely in your browser, very large files use more memory and take longer. Typical songs, podcasts and voice recordings work smoothly.

About this tool

Free online audio speed changer. Speed up or slow down MP3, WAV, M4A and more from 0.5x to 2x without pitch change. Runs 100% in your browser, no uploads.

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