PURESINETone lists & categories
Glowing tiles organize curated lists, each with notes on how the tones are traditionally associated.
- Sleep
- Solfeggio
- Chakras
- Numerology
- Traditional: Organs
- My presets
PureSine – sleep tones, binaural beats and 432 Hz for Android
Pure tones for sleep, focus and calm. Tuned by you.
A beautifully simple frequency generator for Android. Play sleep tones, binaural beats, 432 Hz and solfeggio frequencies, or dial in any tone you like. Everything runs on your phone, offline.
Coming soon toGoogle Play
See features
Free to try · Optional one-time Pro unlock · No ads, no accounts
Features
A frequency generator made for winding down
From meditation tones to relaxing sounds for sleep, PureSine keeps it calm: one screen, glowing controls and nothing you don't need.
Mesh or Alternate, up to 3 tones
Layer tones A, B and C together in Mesh, or cycle through them in Alternate with a switch time you choose.
Binaural beats
Send a slightly different tone to each ear for classic binaural beats. Headphones required.
Search 300 tones by use
Type what you're after, like "sleep", "focus" or "relax", and search a built-in library of about 300 tagged tones and binaural combinations.
My presets & custom tones
Save any setup, star favorites, or build a custom tone with your own name, frequencies and mode.
Session timer with gentle fade
Pick ∞, 5m, 15m, 30m, 1h or 90m, or type your own. Gentle fade eases the tone out at the end.
Lock screen & Quick Settings
Play, pause and stop from the lock screen or notification, and start your last tone from a Quick Settings tile.
Dark & light themes
Deep navy for night, a clean teal light theme for day, or follow your system setting.
Any frequency, offline
Dial in any tone up to 20 kHz with a live frequency EQ. Smart output tips help on phone speakers and Bluetooth.
Free vs Pro
Every feature free. Pay once to remove the limits.
No subscription, no ads. Try everything, and unlock unlimited listening only if you love it.
Free
$0
- Every feature and tone list
- Up to 10 minutes per session
- Up to 30 minutes of listening per day
- Daily time resets at midnight
Planned price
PureSine Pro
$4.99 one-time
- Everything in Free
- Unlimited session length
- Unlimited daily listening
- Pay once, keep it. Restore on a new phone
Pro is a one-time in-app purchase through Google Play. Price is planned and may change before launch; Google Play sets local prices in other countries.
History & culture
A short history of these tones
The tones in PureSine come from very different places: medieval singing lessons, 19th-century acoustics, orchestra tuning debates and modern meditation practice. Here's where each one comes from.
11th century
Do-re-mi begins with a hymn
The Italian music teacher Guido of Arezzo helped singers learn melodies by naming six notes after the first syllable of each line of the Latin hymn Ut queant laxis: ut, re, mi, fa, sol, la. "Ut" later became "do." The syllables named steps of a scale, not fixed pitches, since there was no way to measure pitch in hertz yet.
1839
Binaural beats are discovered
The Prussian physicist Heinrich Wilhelm Dove noticed that two slightly different tones, one played to each ear, are heard as a slow pulsing "beat" that exists only in the listener's perception. For over a century it stayed a scientific curiosity.
1859 – 1885
The search for a standard pitch
Orchestras across Europe tuned to different pitches. In 1859 France fixed its diapason normal at A = 435 Hz, and a conference in Vienna endorsed it in 1885.
1881
Verdi and 432 Hz
Following the advice of composer Giuseppe Verdi, an Italian congress of musicians adopted A = 432 Hz, arguing that a lower pitch was friendlier to singers' voices. The French 435 Hz standard soon won out across Europe.
1880s – 1927
The Western chakra map takes shape
The seven-centre chakra system familiar in the West grew out of older Indian yoga traditions as they were reinterpreted by Theosophical writers, notably C. W. Leadbeater's The Chakras (1927). Pairing each chakra with a particular tone is a later practice of modern sound and meditation circles, and different teachers use different maps.
1939 · 1955 · 1975
440 Hz becomes the standard
An international conference in London in 1939 recommended A = 440 Hz as concert pitch. The International Organization for Standardization adopted it in 1955 and reaffirmed it as ISO 16 in 1975. Some musicians still prefer 432 Hz, and it remains popular in ambient and meditation music.
1973
Binaural beats return to the spotlight
Gerald Oster, a biophysicist at Mount Sinai School of Medicine in New York, published "Auditory Beats in the Brain" in Scientific American. The article gathered more than a century of research and described binaural beats as a tool for studying how the brain processes sound.
1970s – 1990s
The modern "solfeggio frequencies"
The list of "solfeggio frequencies" seen online today (174 to 963 Hz) is not medieval. It traces to Joseph Puleo, who is said to have worked out the numbers from verse numbering in the biblical Book of Numbers, and was popularized in a 1999 book he co-wrote with Leonard Horowitz. More tones were added to the list later. They borrow Guido's syllable names but have no documented link to medieval music.
Today
Where PureSine fits in
PureSine lets you explore all of these as sound. Each built-in tone describes what it is "traditionally associated with" in meditation practice and popular culture, and you're free to make your own.
Sources
- G. Oster, "Auditory Beats in the Brain," Scientific American 229(4), Oct 1973. doi.org/10.1038/scientificamerican1073-94
- "Binaural beats" (history, citing H. W. Dove, Repertorium der Physik III, 1839). simple.wikipedia.org/wiki/Binaural_beats
- "Solfège" (origin, Guido of Arezzo and Ut queant laxis). en.wikipedia.org/wiki/Solfège
- F. Gribenski, "Plenty of pitches," Nature Physics, 2019. doi.org/10.1038/s41567-019-0707-1
- G. W. C. Kaye, "International Standard of Concert Pitch," Nature 143, 1939. doi.org/10.1038/143905a0
- ISO/R 16:1955 and ISO 16:1975, standard tuning frequency. iso.org/standard/3601.html
- "Perfect Pitch: 432 Hz Music and the Promise of Frequency," Journal of Popular Music Studies 33(1), 2021. online.ucpress.edu
- Science Feedback, review of a 741 Hz solfeggio claim (origin with Joseph Puleo, 1970s). science.feedback.org
- "What are Solfeggio Frequencies?" Discovery UK. discoveryuk.com
- K. Leland, "The Rainbow Body: How the Western Chakra System Came to Be," Quest, Theosophical Society in America. theosophical.org
- "Chakras and Shingles: Historical Fragments of the Chakra System in Contemporary Yoga," 2024. doi.org/10.2478/njd-2024-0016
Learn
Understand the sounds you're playing
Short, plain-English guides to binaural beats, solfeggio frequencies, 432 Hz and more.
Binaural beats
What are binaural beats?
Article coming soonSolfeggio
The solfeggio scale explained
Article coming soonTuning
Why 432 Hz?
Article coming soonFAQ
Questions
Do I need headphones?
Only for binaural beats, which need a separate tone in each ear. Everything else plays on your phone speaker or a Bluetooth speaker. Low tones under about 250 Hz are faint on most phone speakers, so PureSine shows a quick tip when headphones or a speaker would sound better.
Does PureSine work offline?
Yes. Every tone is generated live on your phone and the whole tone library is built in. An internet connection is only needed when Google Play processes a purchase or restore.
Is Pro really a one-time purchase?
Yes. Pro is a single in-app purchase through Google Play with no subscription. The planned price is $4.99 in the US.
How do I restore Pro on a new phone?
Sign in to Google Play with the same Google account, then open Settings › PureSine Pro and tap Restore.
Does PureSine collect my data?
No. There are no accounts, ads or analytics. Your presets, history and settings stay on your device. See the Privacy Policy.
Is PureSine a medical device?
No. PureSine is a wellness and lifestyle app: For relaxation and entertainment. Not a medical device. Does not diagnose, treat, or cure any condition.