432 Hz Tone Generator

The generator below is already set to 432 Hz, so pressing play gives you an A that sits a little under a third of a semitone below the concert pitch almost every recording you own was made at. That small gap has collected a large amount of history and an even larger amount of folklore. This page separates the two: what 432 Hz is, where the number came from, and what it does and does not do.

Everything runs in your browser. No audio is ever uploaded.

Where the 432 Hz idea comes from

The number has a real historical thread. Concert pitch drifted upward through the nineteenth century as orchestras chased brightness, and singers complained about it. In 1884 an Italian commission recommended A=432 Hz for the country's orchestras, and Giuseppe Verdi backed the lower pitch in writing as kinder to voices. The reform did not hold: France had already settled on A=435 in 1859, and the international agreement of 1939 landed on 440. Verdi's name has stayed attached to 432 ever since.

The version that circulates today is younger and different. A political campaign in the late 1980s pushed 432 as a moral cause, and the internet later attached it to Schumann resonances, cymatic sand patterns, water crystals and the idea that 432 is written into the geometry of the planet. Those additions are numerology rather than acoustics: they fix one unit, the second, and one reference note, then treat the coincidences that follow as evidence.

What actually changes when you tune to 432 Hz

Musically, less than you might expect. Moving A4 from 440 Hz to 432 Hz shifts every note down by about 31.8 cents, roughly a third of a semitone. Equal temperament is a set of ratios rather than a set of fixed pitches, so a piece retuned this way keeps every interval, every chord shape and every bit of tension exactly as written. Nothing becomes more consonant. The whole thing simply sits slightly lower.

What can change is timbre and feel. On a guitar or a violin, slackening to 432 lowers string tension a little, which softens the attack and can make an instrument sound rounder. Singers sometimes find the top of a part easier to reach. And a recording pitched down to 432 in software is usually also slowed by a fraction of a percent, so part of what listeners report as calm comes from the slower tempo rather than from the pitch.

What the evidence says about the health claims

There is no controlled evidence that 432 Hz has an effect on the body that a different frequency does not. The handful of published studies are small, rarely blinded, and usually compare a piece of calm music at 432 against the same piece at 440 with the listener aware of which is playing. Claims about DNA, cell repair, water structure or the Earth's field have no supporting measurement at all.

That is not the same as saying nothing happens. Sitting still and listening to a steady, quiet tone lowers arousal for most people, and it does so at 440, at 396 and at 528 as well. If a 432 Hz drone helps you settle, or you like how a retuned mix sounds, that is a real preference and reason enough to use it. It simply is not a property of the number.

How to compare 432 and 440 for yourself

The generator above starts at 432 Hz. Press play, then use the 440 Hz preset button to switch between the two without touching the volume, which is the part most comparisons get wrong: even a decibel of level difference makes one option sound better. Alternating every few seconds at a fixed level is the honest test, and most people find the two indistinguishable in character once loudness is matched.

To play at 432 rather than just listen to it, set the reference pitch instead. The tuner on this site has an A4 field that moves from 415 to 466 Hz, so setting it to 432 retunes every string target for you. Remember that the rest of your library is still at 440: an instrument tuned to 432 will beat audibly against any backing track you have not retuned with it.

Where to go next

• Online Tone Generator: one pure tone from 20 Hz to 20 kHz
• 528 Hz Tone Generator: the Solfeggio tone, its origin and the evidence
• 440 Hz Tone Generator: the A=440 reference tone and how it became standard
• Online Tuner: cents readout for guitar, bass, ukulele and violin
• Audio Calculators: note to hertz, BPM to milliseconds, gain to decibels
• Dual Tone Generator: two tones at once for binaural beats