Interactive Solfeggio & Pure Tone Frequency Synthesizer
Tap any reference frequency below (174 Hz – 963 Hz, including 432 Hz and 528 Hz) to synthesize a clean harmonic tone live in your browser.
Select Reference Frequency (Hz)
The nine Solfeggio frequencies
| Frequency | Traditional association |
|---|---|
| 174 Hz | Grounding, a sense of safety |
| 285 Hz | Restoring, renewal |
| 396 Hz | Letting go of fear and guilt |
| 417 Hz | Change, clearing the past |
| 528 Hz | "Love frequency", clarity, transformation |
| 639 Hz | Connection, relationships |
| 741 Hz | Expression, problem solving |
| 852 Hz | Intuition |
| 963 Hz | Stillness, a sense of unity |
These associations come from sound-healing traditions. They are not medical effects and have not been demonstrated in controlled research.
Where do Solfeggio frequencies come from?
The name refers to the syllables ut, re, mi, fa, sol, la, which the 11th-century monk Guido of Arezzo took from the Latin hymn Ut queant laxis to teach singing. The specific frequencies, however, are modern. Medieval music had no fixed pitch standard, so singers could not have used 528 Hz or any other exact value.
The six "core" frequencies (396, 417, 528, 639, 741 and 852 Hz) were popularised in the 1970s by Joseph Puleo and later in the 1999 book Healing Codes for the Biological Apocalypse. The extra tones 174, 285 and 963 Hz were added afterwards.
What does the science say?
There is no solid evidence that any particular Solfeggio frequency heals the body, repairs DNA or changes emotions in a specific way. A handful of small studies, such as a 2018 pilot on 528 Hz music and stress hormones, report interesting results but involve very few participants and need replication.
What is well supported is more general: calm, steady sound you enjoy can help you relax, slow your breathing and create a ritual for meditation or rest. Used that way, Solfeggio tones are a pleasant, low-risk tool.
How to listen
- Keep the soft shimmer on: it blends three voices so the tone feels warm rather than like a test signal.
- Keep it quiet: pure tones become tiring when loud, especially the higher ones.
- Combine with nature: a tone over rain or ocean waves is a popular meditation backdrop.
- Set a session length with the timer so you can close your eyes and not watch the clock.
Frequently asked questions
What are Solfeggio frequencies?
A set of nine tones from 174 Hz to 963 Hz used in meditation and sound-healing practices. Their healing claims are not scientifically established.
Are Solfeggio frequencies ancient?
The syllable names are medieval, but the exact frequencies date from the 1970s and later. Medieval music had no fixed pitch standard.
Which Solfeggio frequency is best?
There is no evidence that one is better than another. 528 Hz is the most popular; choose the tone you find most calming.
Do I need headphones?
No. Pure tones work on speakers and headphones alike.