Play a slightly different tone in each ear and your brain hears a slow beat between them. Pick a brainwave range or a ready session, set the carrier tone, add soft background noise, glide the beat down for sleep and run a timed session. Use headphones for true binaural beats, or switch to monaural or isochronic tones for speakers.
The carrier tone, played only in your left ear.
The carrier plus the beat, played only in your right ear.
Lower carriers feel warmer. Beats come through most clearly with carriers under about 1,000Hz.
The beat moves slowly from where you set it to this target over the first 60% of the session. The session fades in and fades out on its own.
Needs headphones. Each ear gets its own tone.
Each one sets the carrier, the beat, the noise and the length. Press a card to start it straight away.
A binaural beat is not in the audio at all. Your left ear gets one steady tone, say 200Hz, and your right ear gets a tone a few hertz higher, say 210Hz. Neither ear hears a beat on its own.
Deep in the brainstem, a small region called the superior olivary complex is where signals from both ears first meet. It compares the two tones, and the 10Hz gap between them comes through as a slow, soft pulsing, as if the sound is moving inside your head.
That is also why headphones matter. Through speakers both tones reach both ears and mix in the air, which gives a monaural beat instead. This page can play all three kinds, so you can hear the difference for yourself.
The dashed line is the slow rise and fall your brain picks up. Its speed is the gap between the two tones.
Scientists group the brain's electrical rhythms, measured by EEG, into five bands. Binaural beat sessions are named after the band their beat falls in. Press a button to hear a beat from each one.
0.5Hz to 4HzThe slowest waves, strongest in deep, dreamless sleep.
4Hz to 8HzDrowsiness, light sleep and deep meditation.
8Hz to 13HzCalm and awake, often with the eyes closed.
13Hz to 30HzEveryday alert thinking, problem solving and active focus.
30Hz and upFast waves seen during intense focus and memory tasks.
The effect is almost two centuries old. Research into what it does to the brain is far newer, and still going.
The Prussian physicist noticed that two slightly different tones, one in each ear, produced a beat that existed in neither ear alone.
His Scientific American article, Auditory Beats in the Brain, showed the beat is made by the brain and suggested it as a research tool.
Garcia-Argibay and colleagues pooled 22 studies and reported effects on memory, attention, anxiety and pain, depending on frequency and listening time.
Ingendoh, Posny and Heine reviewed 14 EEG studies in PLOS ONE. Five supported brainwave entrainment, eight did not and one was mixed.
Many apps promise a lot. The studies are more careful, and it helps to know where things stand before you rely on a session.
Pooled studies point to modest benefits for some people, mainly lower anxiety and small gains in attention or memory.
The idea that brainwaves lock onto the beat, called entrainment, has inconsistent support. EEG studies disagree and use very different methods.
Many people simply find a steady, pulsing tone easier to relax or focus with than silence. That alone can make a session worthwhile.
Binaural beats are a safe, low-cost thing to try at a gentle volume. They are not a medical treatment. For sleep, anxiety or attention problems, speak with a doctor.
Over-ear or in-ear both work. Press Check Left And Right to make sure each side plays in the right ear.
The tones should sit just above hearing. Louder does not make the beat stronger.
Delta or a wind down for sleep, theta for meditation, alpha to relax, beta to focus.
Try 100Hz to 300Hz. If the tone feels sharp or tiring, lower it.
Most studies use sessions of this length. Sit or lie still and breathe slowly.
Pink or brown noise softens the sound and covers room noise without hiding the beat.
All three pulse at the beat you choose. They differ in how the pulse is made and whether you need headphones.
| Binaural Beats | Monaural Beats | Isochronic Tones | |
|---|---|---|---|
| How it is made | A different tone in each ear. The brain creates the beat. | Two tones mixed together before they reach the ears. | One tone switched on and off at the beat rate. |
| Headphones | Required | Not needed, speakers work | Not needed, speakers work |
| How it sounds | Soft, gentle pulsing that seems to move inside your head | A clear wah-wah pulse in the sound itself | The strongest, most obvious pulse |
| Best for | Quiet sessions with headphones, sleep and meditation | Listening through speakers in a room | Focus sessions and anyone who finds binaural beats too faint |
Binaural beats are safe for most people at a low volume. A few simple rules keep it that way.
The beat works at a whisper. Long sessions at high volume can harm hearing.
Slow beats are meant to relax you. Do not listen while driving or using machinery.
If you have epilepsy, a history of seizures or a heart condition, check with your doctor first.
End the session if you get a headache, dizziness or ringing in your ears.
Binaural beats happen when each ear hears a slightly different tone, such as 200Hz in the left and 210Hz in the right. The brain combines them and you hear a soft beat at the difference, here 10Hz, even though that beat is not in the audio.
Yes. Each ear must hear only its own tone. Through speakers the tones mix in the air and you get a monaural beat instead. If you have no headphones, switch to Monaural or Isochronic on this page.
The evidence is mixed. A 2018 meta-analysis of 22 studies found small effects on anxiety, attention and memory, while a 2023 review of 14 EEG studies found that most did not show the brain following the beat. Many people still find sessions relaxing.
Sleep sessions usually use delta beats from 1Hz to 4Hz, or a glide that starts in alpha or theta and slowly drops into delta. Try the Sleep Wind Down session with brown noise at a low volume.
Focus sessions usually use beta beats from about 14Hz to 20Hz, and some people prefer 40Hz gamma. Results vary from person to person, so try a few and keep the one that helps you work.
Most people find 100Hz to 300Hz comfortable. The beat comes through best with carriers under about 1,000Hz. If the tone feels sharp or tiring, lower the carrier.
15 to 30 minutes is a common session length and matches what many studies use. Sleep sessions can run longer with the timer set so the sound fades out by itself.
For most people, yes, at a low volume. Do not listen while driving. If you have epilepsy, a history of seizures or a heart condition, ask your doctor before using them.
Binaural beats use a different tone in each ear and need headphones. Monaural beats mix the two tones before they reach your ears. Isochronic tones switch one tone on and off. The last two work on speakers.
No. White, pink and brown noise play underneath the tones to soften them and cover room sounds. Keep the noise a little quieter than the tones so the beat still comes through.
Yes. Set your carrier, beat, beat type and noise, choose 30 seconds, 1 minute or 2 minutes and press Download WAV. The stereo file keeps each tone in its own channel, so play it with headphones.
Yes. It runs in any current browser on phones, tablets and computers. On iPhone, turn off silent mode, and keep the screen on during a session because some phones pause audio when the screen locks.
Real problems from listeners, answered and checked by the Sound Test Audio Team.
Research on binaural beats for sleep is mixed, and results vary between people. Keep the volume very low, use a timer and skip earbuds in bed if they are uncomfortable.
Read the full answerBinaural beats need stereo headphones, with a different tone in each ear. The wobble you hear is the beat. Speakers or mono audio will cancel the effect.
Read the full answerDelta beats, 1 to 4 Hz, are often used for sleep. Keep volume low, use a timer and take the headphones off if they hurt.
Read the full answerBinaural beats need headphones because each ear hears a different tone. Isochronic tones are pulses that work on speakers. Which is better is personal.
Read the full answerMany people use alpha around 10 Hz for calm focus and beta for alert work. Evidence is mixed, so treat it as a personal preference.
Read the full answer