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Audio Speed and Pitch
Change speed without changing pitch, or shift pitch by semitones without changing speed.
Free, no uploads, no sign-up. Runs 100% in your browser.
How Audio Speed and Pitch works
The sound is processed by ffmpeg compiled to WebAssembly, running in your browser. The engine (about 30 MB) downloads the first time and is cached after that, so nothing is ever uploaded. Tempo uses the atempo filter. Pitch changes resample the audio and correct the tempo so the length stays the same.
Input: MP3, WAV, M4A, OGG, FLAC, AAC, OPUS, MP4, MOV, WEBM. Output: MP3, WAV, M4A, OGG, FLAC, MP4.
How to use Audio Speed and Pitch
- Drop an audio or video file.
- Choose Speed, Pitch or Both.
- Set the amount.
- Apply, listen and download.
Tips
- WAV is lossless but large; MP3/AAC/OGG are compact for sharing.
- Engines load on first use and are cached afterwards.
Audio Speed and Pitch FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
Related tools
- Audio Editor & Trimmer: Trim, fade in/out, change volume and export with a waveform.
- Audio Converter: Convert MP3, WAV, OGG, AAC, FLAC and M4A.
- Video Speed: Speed up or slow down a video from 0.25× to 4×.
- Volume Booster and Normalizer: Make quiet audio or video louder, or even out loudness to a standard level (EBU R128).