The Speed Changer
Listen to lectures at 1.5x, slow a song down to practice, or shift the pitch for a tape effect.
1 · Choose your files
Drag & drop audio or video files here, or click to browse
Up to 5 files, max 200 MB each
2 · Set the speed
All processing runs on your own device with ffmpeg compiled to WebAssembly; nothing is uploaded.
3 · Collect your files
Results appear here with a player. Download them one by one or grab everything as a ZIP.
How to change the speed of an audio file online
- Add up to 5 audio files to the box above.
- Pick a speed and decide whether the pitch should stay the same.
- Click Change speed, listen to the result and download.
Frequently asked questions
Does changing the speed change the pitch?
Only if you want it to. By default the pitch is kept, so voices and instruments sound natural, just faster or slower. Untick the option to shift the pitch along with the speed.
Can I slow down a song to practice?
Yes. 0.75x or 0.5x with the pitch kept keeps the notes in the same key while giving you time to follow.
Is this private?
Yes. The processing happens entirely in your browser. Your files are never uploaded.
More free tools: Converter · Trimmer · Merger · Compressor · Volume · Silence