432 Hz Converter

Upload the file here, leave the target on 432 Hz, choose whether you want the tempo preserved, and export as MP3 or WAV. Nothing is installed, no account is needed, and the audio never leaves your browser. The conversion from a standard A=440 recording is a shift of −31.77 cents, which is a little under a third of a semitone.

With the varispeed method, yes — and most converters do this without telling you. Retuning by resampling moves pitch and tempo together, so a 432 Hz conversion runs about 1.82% slower and the file gets about 1.85% longer: a 3-minute track gains roughly 3.3 seconds, and 120 BPM becomes 117.8 BPM. Switching this tool to Keep original tempo time-stretches the audio to cancel that, so the running time is unchanged and only the pitch moves.

They are different trades rather than better and worse. Varispeed is exactly what happens when you slow a tape or a record: nothing is reconstructed, so the timbre stays completely natural, but the track changes length. Tempo-preserving retuning keeps the running time by overlapping small grains of audio, which is close to transparent at a shift this small but can very slightly soften sharp transients like drum attacks. Use varispeed if you want the most natural sound and do not care about duration; use tempo-preserving if the audio has to stay in sync with video or another track.

This is the most confused question in the whole topic, and different tools silently do opposite things. If 528 Hz is read as C5, then A lands at about 444 Hz and the shift is a gentle +15.7 cents. If 528 Hz is read as A4 itself, the shift is +315.6 cents — a minor third up, which transposes the entire song and sounds nothing like a subtle retune. This tool offers both and labels which is which, so you can pick deliberately rather than discover it after exporting.

The ratio is 432/440 = 0.981818, which works out to −31.77 cents, or −0.3177 of a semitone. For comparison, a semitone is 100 cents, so the move is a bit less than a third of the distance between two adjacent keys on a piano.

In a direct comparison, yes. The smallest pitch difference most listeners can reliably detect is around 5 to 8 cents, so a 31.77-cent shift is roughly four to six times that — clearly audible when you switch between the two. On its own, though, it is a different matter: identifying whether a track you are hearing for the first time is at 432 or 440 requires absolute pitch, which most people do not have. That gap between "obvious in comparison" and "unidentifiable in isolation" explains a lot of the disagreement about this topic.

No, and this is the fact most pages on the subject get wrong. Retuning moves the reference that every note is measured from; it does not change the relationships between the notes. An octave is still exactly 2:1, a fifth is still a fifth, and the chord shapes and melody are untouched. A song retuned to 432 Hz is the same song at a slightly lower absolute pitch, not a differently constructed one.

Not much, and it is weaker than most pages imply. There is no systematic review or meta-analysis on the subject. What exists is a handful of small trials, most with between 12 and 54 participants, several from the same research group, mostly described by their own authors as pilots, and some carrying published corrections. A 2019 crossover study of 33 people found a heart-rate difference of about 5 beats per minute at borderline significance, with blood pressure changes the authors themselves reported as not significant. A 2020 dental study found that music reduced anxiety substantially but that 432 and 440 performed about the same, with only a cortisol measure differing. And a 2025 crossover study of kickboxers found 440 Hz outperformed 432 Hz on performance and mood. Nothing supports claims about DNA, water, or the structure of the universe.

No. The claim does not survive its own timeline. A=440 was recommended by the physicist Johann Heinrich Scheibler and approved at a Stuttgart congress in 1834, a century before the Nazi party took power. The 1939 conference that settled on 440 was hosted at the BBC in London, with delegates from France, Germany, the Netherlands, Italy and England — France and Italy attended rather than being excluded, as the story usually claims. Fact-checkers have also noted that American musicians adopted 440 Hz in 1917. It became an ISO recommendation in 1955 and a full standard, ISO 16, in 1975.

Partly, and the real story is more interesting than the myth. Verdi campaigned hard against rising concert pitch, which was straining singers' voices, and he wrote his Requiem for A=435 — the pitch France had set by law in 1859. When an Italian commission proposed rounding 435 down to 432 for mathematical convenience, Verdi wrote that the difference was "so small" and that what he actually wanted was a single standard adopted everywhere. He was a campaigner for standardisation and against pitch inflation, not a believer in a special frequency. The name "Verdi tuning" was attached to 432 Hz by a campaign in 1988, long after his death.

No. The Schumann resonance is an electromagnetic phenomenon — a standing wave in the cavity between the Earth's surface and the ionosphere, excited by lightning — with a fundamental of about 7.83 Hz. It is not a sound. The usual argument is that 8 × 54 = 432, but the measured value is 7.83 rather than 8, and 432 divided by 7.83 is 55.17, not a whole number. The connection only works if you round a physical constant first.

Then converting from an assumed 440 will land you somewhere other than 432, because retuning is relative rather than absolute. Recordings drift for real reasons: tape machines run slightly off, older recordings predate reliable standardisation, and some orchestras tune deliberately sharp at 442 or 444 Hz. That is why the source tuning is adjustable here. If you can identify a sustained note and check it against a tuner, set the source to match before converting.

No — there was no single historical standard at all, which is the genuinely interesting part. Before standardisation, pitch varied enormously by city and instrument: a Versailles organ from 1795 sat around 390 Hz, a Paris Opera fork from 1810 around 423 Hz, an 1855 fork at 449 Hz, and La Scala reportedly reached 451 Hz. British "old philharmonic" pitch was about 452 Hz. One 1822 French tuning fork did measure 432 Hz, but it was one point in a very wide spread rather than a lost universal standard. An analysis of 85 historical pitch samples reportedly found none measuring exactly 432 Hz.

This tool retunes existing recordings, not instruments. To play at 432 Hz yourself, set your tuner's reference or calibration to 432 Hz — most electronic and app tuners have this setting, often labelled A4 or calibration — and tune normally from there. A piano needs a technician, and moving a whole piano by 32 cents is a real job rather than an adjustment. If you want to play along with a 432 Hz track, retuning your instrument is the correct approach; converting the track to 440 to match your instrument works just as well.