Free 432 Hz Converter
Retune a 440 Hz track to the 432 Hz standard.
What is this tool
AudioToolKit converts audio from 440 Hz to 432 Hz online for free, in your browser. It applies the exact -0.32 semitone pitch shift with a time-stretch that keeps the tempo unchanged, landing the A4 note on 432 Hz. The retuned track downloads as MP3 or WAV, and the file is processed entirely on your device — no upload, no install, no account.
Drag and drop your file here
or
MP3, WAV, M4A, AAC, OGG, FLAC, AIFF, AIF, OPUS, WMA, AMR — up to 25 MB per file
Output
432 Hz-tuned MP3 or WAV
Accepted formats
.mp3, .wav, .m4a, .aac, .ogg, .flac, .aiff, .aif, .opus, .wma, .amr
Why use this free tool
432 Hz is the alternative tuning many listeners prefer, described as warmer and easier on the ears. Converting means shifting the pitch by -0.32 semitones — inaudibly small, but exactly the interval between the two standards.
How does the free 432 hz converter work?
- 1
Upload the 440 Hz track.
- 2
Press Process — the -0.32 semitone shift is applied automatically.
- 3
Download the retuned file.
Frequently asked questions
Why -0.32 semitones?
432/440 in log2 is -0.3177 semitones. Rounding to -0.32 lands the A4 note on 432 Hz.
Does the tempo change?
No, the shift is time-stretch compensated.
Local processing?
Yes, in your browser.
Related tools
More answers in the Help Center.