528 Hz and the solfeggio frequencies: where they came from, what has been tested, and why I use them
The frequencies are usually sold as ancient. They are younger than that, and more interesting. A composer who uses them every day on where they come from, what the early research shows, and why they work in a routine.
Type 528 into a search engine and the suggestions fill in before you finish: love frequency, DNA repair, miracle tone. There are Spotify artists whose entire output is that one note held for ten hours. I use it. The 528 Hz routine in the app is one of the ones people write to me about most, and I have played the frequency under my own compositions since before the app existed. I also know where the number comes from, and the real story is more recent than the one being told, and in its own way more interesting.
Where the solfeggio frequencies come from
The solfeggio frequencies appear in print for the first time in 1999, in a book called Healing Codes for the Biological Apocalypse by Leonard Horowitz, a dentist, and Joseph Puleo, a naturopath. Puleo describes deriving six numbers from the Book of Numbers, chapter seven, verses twelve to eighty-three, the passage listing the offerings of the twelve tribes. He reduced the verse numbers by repeatedly adding their digits, found a repeating pattern of threes, sixes and nines, and built frequencies from it: 396, 417, 528, 639, 741 and 852. The three others now included in the set, 174, 285 and 963, were added afterwards to round the scale out. Nothing in the derivation involves music, or a tuning fork, or any text older than the book itself.
The claim that these tones are ancient rests on a real piece of music history that has been stretched further than it goes. Around 1030, the Benedictine monk Guido of Arezzo took a hymn to St John the Baptist, Ut queant laxis, in which each line begins one step higher than the last, and used its opening syllables, ut, re, mi, fa, sol, la, to teach singers the steps of the scale. That is where do-re-mi comes from. It says nothing about frequency, because frequency as a measurable quantity did not exist; medieval pitch was relative, set by whichever singer began, and it varied from town to town. The hertz was not defined until the nineteenth century, and the standard that fixes the A above middle C at 440 was agreed at a conference in London in 1939 and formalised by the ISO in 1955. There was no 528 in the eleventh century because there was no way to have one. And at the modern standard, the note C above middle C sits at 523.25 Hz, so 528 does not correspond to "mi" or to any note in the scale Guido was teaching.
What the studies on 528 Hz show
There are two experiments, both small, and both encouraging as far as they go. In 2018 a Japanese team played nine adults, eight of them women, the same piano piece tuned to 528 Hz on one day and to the standard 440 Hz on another, for five minutes each. After the 528 version, salivary cortisol fell, oxytocin rose and self-rated tension dropped; after the 440 version, nothing changed significantly. Nine people and five minutes is a pilot, and it deserves a larger repeat, but the direction is the one I would hope for. In 2017 a laboratory in Tehran exposed human brain cells in a dish, damaged with alcohol, to a 528 Hz tone at eighty decibels and reported fewer of them died. That is a cell study at a volume you would not sit in, so it says little about a person in a bedroom, but it is part of the picture.
So far, that is the primary research on 528 Hz. The DNA repair claim is a separate story: it traces to Horowitz's own books, which cite a water chemist named Lee Lorenzen and an unpublished experiment from the 1990s in which vials of DNA were exposed to various music and their light absorption measured. That experiment did not test 528 Hz, was never peer-reviewed, and did not involve living cells, so I do not repeat the claim. What sound reaches with good evidence is the nervous system, and for skin that is the route that counts.
There is a nearby study worth knowing about, because it is better designed and often confused with the solfeggio literature. In 2019 an Italian team played 33 people the same film music tuned to 440 and to 432 Hz, double-blind, and found the 432 version was followed by a small drop in heart rate, around five beats a minute, and better self-reported concentration. It is a pilot, the difference between the tunings is barely audible, and the authors ask for a larger trial. It says nothing about 528, though it does hint that a body can respond to a tuning the ear cannot consciously pick out.
Why Skin Resonance uses 528 Hz
Because the tone does real work, and the pitch is part of how it feels. What the app plays during a solfeggio step is a sustained sine tone with a slow pulse in its loudness, six times a second in the 396 routine, eight in the 528, over a bed of soft brown noise. The pulse is the part with the clearest evidence. A beat in that theta range has been shown, in a 2017 EEG study, to increase theta activity across the scalp within ten minutes, and slow, steady sound of almost any kind produces the relaxation effects that the sound healing article goes through. A tone at 528 Hz carries that pulse beautifully, and so, in the binaural steps, does the 7.83 Hz beat that has its own history. I chose the solfeggio values because they are the language people already use, because the one pilot study on 528 Hz found what I would hope to find, and because, as a composer, those particular pitches sit well to my ear in a chord with the noise bed underneath. A tone you find beautiful is one you will lie down under again tomorrow, and repetition is where the benefit lives.
What I will not tell you is that the tone repairs your cells, or that a medieval monk tuned it, because neither has been shown. I can tell you that the 528 routine calms many of the people who use it, that the calm is real and measurable, and that it comes from twenty minutes of low, steady sound with your eyes closed, at a pitch that happens to be lovely.
People curious about frequencies are the readers I most want on this site, and they deserve the real history alongside the tones. The history dates from 1999, the tones are lovely, and the calm they bring is the part the research supports. I would rather you knew all three before you put the headphones on.
To hear a solfeggio step as the app plays it, with the pulse underneath, the free ten-minute routine opens with one.
Calm for stressed skin: the free 10-minute routine
The same routine as the free try page, on YouTube: 396 Hz to settle, 7.83 Hz Schumann, then 4 Hz theta. Headphones on for steps 2 and 3.
Watch on YouTube →Sources & further reading
- Horowitz LG, Puleo JS. Healing Codes for the Biological Apocalypse. Sandpoint, ID: Tetrahedron Publishing Group; 1999.
- Guido of Arezzo. Epistola de ignoto cantu (c. 1030). Summarised in: Encyclopaedia Britannica, Guido d'Arezzo. Britannica
- International Organization for Standardization. ISO 16:1975, Acoustics — Standard tuning frequency (Standard musical pitch). History summarised at Wikipedia: A440
- Akimoto K, Hu A, Yamaguchi T, Kobayashi H. Effect of 528 Hz music on the endocrine system and autonomic nervous system. Health 2018;10(9):1159–1170. SCIRP
- Babayi T, Riazi GH. The effects of 528 Hz sound wave to reduce cell death in human astrocyte primary cell culture treated with ethanol. Journal of Addiction Research & Therapy 2017;8(4):335.
- Calamassi D, Pomponi GP. Music tuned to 440 Hz versus 432 Hz and the health effects: a double-blind cross-over pilot study. Explore 2019;15(4):283–290. PubMed
- Jirakittayakorn N, Wongsawat Y. Brain responses to a 6-Hz binaural beat: effects on general theta rhythm and frontal midline theta activity. Frontiers in Neuroscience 2017;11:365. PubMed
- Ingendoh RM, Posny ES, Heine A. Binaural beats to entrain the brain? A systematic review. PLoS ONE 2023;18(5):e0286023. PMC
Elsewhere on the web
- Encyclopaedia Britannica: Guido d'Arezzo, the real history behind do-re-mi.
- An online tone generator: type 528, then 523.25, and hear for yourself how little separates them.
- Sound Medicine Academy: the solfeggio claims against the science, a fair review from inside the sound-therapy world.
Skin Resonance is a wellness web app, not a medical device, and does not diagnose, treat or cure any condition. For a diagnosed skin condition, please see a dermatologist.
Frequently asked
Are the solfeggio frequencies ancient?+
No. They were first published in 1999 by Leonard Horowitz and Joseph Puleo, derived from the verse numbers of Numbers 7:12–83 by adding digits. The medieval hymn that gave us do-re-mi has no frequencies attached to it, because pitch was not measured in hertz until the nineteenth century.
Does 528 Hz repair DNA?+
That has not been shown. The claim comes from Horowitz's books and an unpublished 1990s experiment on DNA in vials that did not test 528 Hz. What sound does reach, with good evidence, is the nervous system, and that is where the skin benefit comes from.
Has 528 Hz been tested at all?+
Twice, in small early studies: nine adults listening for five minutes (cortisol fell, oxytocin rose, tension dropped) and a cell study in the laboratory. Both point the right way and both need larger repeats. A better-designed pilot on 432 Hz tuning found a small drop in heart rate.
So why does Skin Resonance use these frequencies?+
Because the working part of a solfeggio step is the slow pulse in the tone's loudness and the twenty minutes of steady sound around it, both of which have evidence, and the pitch itself is a musical choice that sits well with the noise bed and that people find beautiful, which is what brings them back to it.