Three simple steps
How to change audio tempo
- 01
Choose a supported audio file from your device. The file stays in your browser and is not uploaded to ToolYogi.
- 02
Select a speed from 0.5× to 2×. If you know the original BPM, enter it to see the calculated target BPM.
- 03
Process the audio, preview the tempo-changed result and download the WAV file.
What is tempo changing?
Tempo changing alters how quickly audio plays while aiming to preserve the original musical pitch. Slower settings make the recording longer; faster settings make it shorter.
How is target BPM calculated?
If you enter the original BPM, ToolYogi multiplies it by the selected speed. For example, a 120 BPM track at 1.25× becomes approximately 150 BPM.
What works best?
Moderate changes usually sound most natural. Full mixes, stems and rhythmic material can work well, but extreme slowdowns or speed-ups can introduce smearing, transient changes or other artifacts.
Does ToolYogi upload my audio?
No. Audio decoding, time stretching and WAV generation run locally in your browser. ToolYogi does not create a cloud copy or conversion history for this tool.
A little more clarity
Frequently asked questions
Is the Tempo Changer free?
Yes. You can change the tempo of supported audio files without creating an account.
Can I slow down music without lowering the pitch?
Yes. The current tool uses time-stretching designed to change duration while keeping pitch roughly stable.
Can I speed up a 100 BPM track to 125 BPM?
Yes. Set the speed to 1.25×. If you enter 100 as the original BPM, the tool will display 125 BPM as the target.
Does changing tempo affect quality?
It can. Large changes are more likely to introduce artifacts. Smaller changes generally sound more natural.
What format is downloaded?
The processed result is exported as a stereo WAV file.
Is my audio stored?
No. This tool processes the selected audio locally in the browser and does not upload or store it on ToolYogi servers.
Open-source local processing
Tempo changing uses the MIT-licensed @audio/stretch project and a transient-aware time-stretching algorithm designed for music. The selected audio stays in the browser.