The 528 Hz tuning fork.
What note is 528 Hz?
In today's standard tuning, with A = 440 Hz and equal temperament, the C an octave above middle C (C5) is 523.25 Hz. 528 Hz lies about 16 cents above it. A semitone has 100 cents, so 528 Hz is a C that is a sixth of a semitone sharp: close enough to be heard as a C, far enough that a tuner will show it as slightly high.
There is a tidier way to arrive at the number. In just intonation, where intervals are tuned to simple whole-number ratios, the C that forms a pure major sixth below A = 440 Hz is 264 Hz. Double it and you get 528 Hz. So 528 Hz is a perfectly ordinary pitch in one historical way of tuning a C major scale. There is nothing hidden in the number itself.
Like any fork, a 528 Hz fork produces an almost pure sine tone. Its sound wave in air at room temperature is about 65 centimetres long. That is physics, and it is true of every 528 Hz tone, whether it comes from a fork, a flute or a speaker.
What are the Solfeggio frequencies?
The term describes a set of six tones, sometimes extended to nine. Solfeggio tuning fork sets are sold in both versions.
| Frequency | Syllable in the claim | Nearest note at A = 440 Hz |
|---|---|---|
| 396 Hz | Ut | G4, 18 cents sharp |
| 417 Hz | Re | G sharp 4, 7 cents sharp |
| 528 Hz | Mi | C5, 16 cents sharp |
| 639 Hz | Fa | between D sharp 5 and E5 |
| 741 Hz | Sol | F sharp 5, 2 cents sharp |
| 852 Hz | La | between G sharp 5 and A5 |
Nine-fork sets usually add 174, 285 and 963 Hz. As the table shows, several of the tones fall between the notes of a standard scale. Played together they do not form a conventional musical scale, which is one reason the sets are used for listening and ritual rather than for tuning instruments.
Where the Solfeggio frequencies come from
The syllables are genuinely old. In the 11th century the music theorist Guido of Arezzo named the six notes of the hexachord after the first syllable of each line of the Latin hymn Ut queant laxis: ut, re, mi, fa, sol, la. Each line begins one step higher than the last. "Ut" later became "do", and a seventh syllable was added. This is the origin of the do-re-mi that singers still use.
The frequencies are not old. They were popularised by Joseph Puleo and Leonard Horowitz in their 1999 book Healing Codes for the Biological Apocalypse. The book presents them as the product of numerology: the digits of each frequency reduce to 3, 6 or 9 (for 528: 5 + 2 + 8 = 15, and 1 + 5 = 6). Guido's syllables named positions within a scale, not fixed pitches. Pitch was not standardised in his time, and the practice of measuring notes in vibrations per second came centuries later. So there is no historical record linking these numbers to medieval chant.
The claims about 528 Hz, and the evidence
528 Hz is often called the "love frequency" or the "miracle tone", after the line Mira gestorum in the hymn. The most repeated claim is that it repairs DNA. Others say it reduces stress or brings the body into harmony. These are claims made by practitioners and sellers, not established findings.
What the evidence shows: there is no robust scientific evidence that 528 Hz, as a tone or as a tuning fork, repairs DNA or heals anything. The research that is cited is thin. One frequently quoted study, published in the journal Health in 2018, compared music tuned to 528 Hz and to 440 Hz in nine healthy adults over five minutes of listening and reported differences in some saliva markers and mood scores. The study used music, not a tuning fork. A small pilot with nine participants cannot establish an effect, and we found no larger independent trial that confirms it.
What it does not rule out: people can find a sound pleasant, and listening to music can be a pleasant pause. That is true of many sounds and says nothing special about the number 528. If you have a health concern, see a doctor. A tuning fork is not a treatment.
Buying a 528 Hz tuning fork or a Solfeggio set: what to check
- The stamped frequency. A good fork is marked with its frequency. You can check it with any chromatic tuner app set to A = 440 Hz: a 528 Hz fork should read as C, about 16 cents sharp.
- Weighted or unweighted. Weighted forks have small masses on the prongs. They have a quieter tone and are mostly pressed onto a surface. Unweighted forks are louder and meant for listening.
- Material. Steel and aluminium alloys are common. The material affects how long and how loud the fork rings, not what the frequency means.
- Claims on the box. A seller who promises DNA repair or healing is making a claim no one has shown to be true. Judge the fork as an object: accuracy, finish, sound.
Why our Fork is 432 Hz, not 528 Hz
The Cosmic Wishing Fork is tuned to 432 Hz, a slightly lower A. We chose it for its tone and because choosing a pitch is a small, deliberate act. We make no claims about effects for any frequency, ours included. The Fork is a ritual object, not a medical device. It is not on sale yet: join the list to hear when it opens.
Questions
What is a 528 Hz tuning fork used for?
Mostly for listening, meditation and sound practices, often as part of a Solfeggio set. It is not used for tuning instruments or for medical tests, where 440 Hz, 512 Hz and 128 Hz are standard.
Does 528 Hz repair DNA?
No. There is no robust scientific evidence that 528 Hz or any other audible frequency repairs DNA. The claim goes back to a 1999 book, not to research.
Is 528 Hz a C?
Close to one. In standard tuning C5 is 523.25 Hz, so 528 Hz reads as a C about 16 cents sharp. In just intonation based on A = 440 Hz, 528 Hz is exactly a C.
Are the Solfeggio frequencies ancient?
The syllables ut, re, mi, fa, sol, la date from the 11th century. The frequencies attached to them were published in 1999 and have no documented medieval source.