How to use the Audio Speed Changer
- Choose the audio file.
- Pick a speed: 1.25×–1.5× for podcasts, 0.75× for practice.
- Click Change speed.
- Download the new file.
Pitch stays the same
The speed changer uses time-stretching, so voices and instruments keep their natural pitch at every speed. A 60-minute lecture at 1.5× becomes 40 minutes.
Good to know
Speed is changed with time-stretching, which keeps pitch constant. Very large changes (below 0.75× or above 2×) can make music sound slightly phasey; speech stays clear.
Supported files
MP3, WAV, M4A, AAC, OGG, OGA, FLAC, OPUS, WMA, AIFF, AIF, AIFC, ALAC, AMR, AC3, MP2, M4B, M4R, CAF, AU, WEBA, 3GA, APE and VOC. Files up to 1 GB each.
Frequently asked questions
Can I change the pitch instead?
Not with this tool; it changes tempo only.
How much does the Audio Speed Changer cost?
Nothing. It is free with no registration, no watermark and no limit on how many files you convert.
Is my file uploaded to a server?
No. The converter runs inside your browser using WebAssembly, so your file is processed on your own device and never sent to us or anyone else.
Can I use it on my phone?
Yes. Open the page in your phone's browser and choose a file. Phones have less memory than computers, so very large files are better converted on a laptop or desktop.