Binaural beats generator: for sleep, calm and focus

What are binaural beats, in plain words

Picture two strings tuned almost the same. When they sound together, the sound starts to swell and fade slowly. That swelling is called a beat, and its rate equals the difference between the two frequencies.

A binaural beat is the same thing, except that it is born in the head, not in the air. One tone goes to the left ear, a slightly different one to the right. Each ear hears only its own tone, the brainstem combines them, and you hear a third sound: a slow pulse that is not actually present in either earphone.

The phenomenon was described in 1839 by the German physicist Heinrich Wilhelm Dove and became widely known after the biophysicist Gerald Oster's article in Scientific American in 1973. Binaural means “with two ears”.

How the binaural beats generator works

The generator makes the sound in your browser, so there is nothing to download and the frequencies are exact. You choose two things: the carrier tone and the beat frequency. With a 200 Hz carrier and a 6 Hz beat, the left ear hears 200 Hz, the right ear 206 Hz, and the brain hears a 6 Hz pulse.

The carrier only decides how the sound feels: lower is softer, higher is brighter. The beat frequency is what matters for the effect, so pick a carrier you find pleasant.

The isochronic tones mode works differently: one tone is switched on and off at the chosen rate. The pulse is then in the sound itself, so no headphones are needed.

• Both tones must be below 1000 Hz, otherwise the brain no longer combines them.
• The beat is clearly heard when the difference is roughly 1 to 30 Hz.
• Set the volume so the tone is barely audible. A louder sound does not make the effect stronger.

Which frequency to choose: delta, theta, alpha, beta or gamma

The electrical activity of the brain is divided into five frequency bands, and each is seen more often in a certain state. Binaural beats are named after the same bands: you choose the beat that matches the state you are after.

The borders between the bands are not strict, and people differ. If 10 Hz calms you and 6 Hz makes you sleepy, that is normal. Try a few frequencies and keep the one after which you feel the way you wanted. Each band has its own page on this site: start with “Brain waves” for the overview, then read the pages on delta, theta, alpha, beta and gamma waves for what each rhythm does in the brain.

Binaural beats benefits: what the research shows

The strongest evidence is a 2019 meta-analysis in which Spanish researchers pooled the results of 22 studies. The overall effect of binaural beats on memory, attention, anxiety and pain perception was medium (g = 0.45), significant and consistent across studies. The authors concluded that binaural-beat exposure is an effective way to affect cognition and to reduce anxiety and the perception of pain, without prior training.

The same analysis showed three practical things. First, longer listening works better. Second, listening before the task, or before and during it, gives better results than during the task only. Third, the beat does not have to be hidden under white or pink noise: an unmasked beat works just as well.

An anxiety study worth knowing: in a UK hospital, patients waiting for day surgery were randomly split into three groups. Anxiety fell by 26.3% in those who listened to a recording with binaural beats, by 11.1% in those who heard the same recording without them, and by 3.8% in those who listened to nothing.

Newer pooled analyses point the same way. A 2023 meta-analysis of 15 studies on memory and attention found a similar medium effect (g = 0.40), although results for theta and beta beats conflicted. A 2026 meta-analysis of 13 randomised trials of theta beats, with 630 participants, found less pain than in control groups (SMD −0.53, from four trials with 173 people), but rated the certainty of that evidence as low and could not pool the anxiety and memory results at all. To put g = 0.45 in plain terms: the average listener ended up better off than about two thirds of the people in the control groups. That is a real, noticeable effect, and far smaller than the transformation many apps promise. The table below collects the key numbers.

• Less anxiety and tension before a stressful event.
• Better attention and memory when you listen before the task.
• Weaker perception of pain.
• Better self-rated sleep quality.

It is fair to say what studies have not settled yet. In a 2023 review of 14 studies that measured brain waves themselves, five showed that brain activity follows the beat, eight did not, and one gave mixed results. In other words, the effect on how people feel and perform is measured better than the mechanism behind it. The section on binaural entrainment below looks at this question more closely.

Binaural entrainment: does the brain wave follow the beat?

Entrainment is the idea behind almost every binaural app: play a 10 Hz beat and the brain starts to oscillate at 10 Hz, moving into the alpha state. The part of this that can actually be measured is called a steady-state response: an EEG rhythm that follows a rhythmic sound while it plays and fades when it stops.

For a sound that really pulses, this response is well established. Since 1981 it has been known that sounds repeated about 40 times a second make the hearing brain answer with a clear 40 Hz wave, even at volumes close to the threshold of hearing. Doctors use this response for objective hearing tests.

For binaural beats the picture is weaker. In a 2005 study, a 40 Hz binaural beat did produce a 40 Hz brain response, but only with low carrier tones around 400 Hz; above 3 kHz it could no longer be detected, and even at its best it was smaller than the response to the same beat physically present in the sound. When a 2023 review put all the EEG studies together, brain activity followed the beat in five of 14 studies, did not in eight, and gave mixed results in one.

Two things follow from this. First, even where an EEG response appears, it is a response of the hearing system recorded while the sound plays; it does not show that the whole brain has switched into an “alpha mode”. Second, the effects in the meta-analyses were measured on how people felt and performed, not on the EEG. People respond to binaural beats even though their brain waves often do not copy them.

What the bands mean in the first place is explained on the page “Brain waves”, and each rhythm has its own page: delta, theta, alpha, beta and gamma waves. Read them with one distinction in mind: a rhythm the brain produces in a certain state is not the same as a rhythm you can switch on from outside.

• Keep the carrier low, a few hundred hertz: in the 2005 study the brain response was present at about 400 Hz and gone above 3 kHz.
• If you want the brain to follow a rhythm as strongly as possible, choose isochronic tones: a pulse that is in the sound itself gives a stronger response than a binaural beat.
• Judge the result by how you feel and work after a week of listening, not by the promise that a beat “sets” your brain to a band.

Binaural beats for sleep

For sleep people use delta beats, most often 2 to 3 Hz. In a pilot study by Iranian researchers, 20 students listened to a delta beat for a week: they fell asleep faster, woke less often at night, slept longer and rated their sleep and their mornings better. Anxiety and anger decreased as well.

In a study at the German Sport University, 15 young football players slept with 2–8 Hz binaural beats for eight weeks. Their ratings of sleep quality, awakening and motivation improved, while a control group that slept without the sound showed no change.

Not every study is that clear-cut. In a double-blind trial in South Korea, 43 people with mild insomnia listened to music with or without theta beats before bed for two weeks. Sleep improved in both groups, and the difference between them was not statistically significant. So treat binaural beats as one tool next to darkness, a cool room and a regular bedtime, not as a replacement for them.

• Choose the delta preset (2 Hz) and a 30-minute timer; the sound fades out by itself.
• Listen lying down, with your eyes closed.
• If headphones get in the way, use isochronic tones through a speaker or sleep headphones.

Binaural beats for focus and studying: beta and 40 Hz

For attention people use beta (14–30 Hz) and gamma (40 Hz) beats. In a Leiden University study, people who listened to a 40 Hz beat focused on detail better than those who heard a constant tone. In a memory study, participants recalled more words after a 20 Hz beta beat and fewer after a 5 Hz theta beat than the control group.

Hence a practical rule: slow beats do not suit the time before study and work. Keep theta and delta for the evening, and listen to a beta or gamma beat for 15 minutes before you start.

40 Hz is often mentioned together with research at the Massachusetts Institute of Technology. That work uses a different method, a light flickering and a sound clicking at 40 Hz, not binaural beats, so those results cannot be applied to binaural beats directly.

Binaural beats and ADHD: what the studies found

Many people with ADHD try binaural beats as a study aid, and beta beats around 15 Hz are often recommended for it online. The research is small, so it is worth knowing exactly what it found.

In a double-blind pilot trial published in 2010 (Kennel and colleagues), 20 children and adolescents with ADHD listened for 20 minutes three times a week for three weeks, either to a recording with binaural beats or to the same recording without them. On attention tests the two groups did not differ. Parents and participants did report fewer homework problems and found the method easy to use.

In a pilot trial with university students who were taking medication for ADHD, presented as a conference abstract in 2022, one group studied with a 15 Hz beat (400 Hz in the left ear, 415 Hz in the right) and the other with two identical 400 Hz tones. After four weeks, only self-rated study performance improved in the beat group. The ADHD symptom scale, a mind-wandering scale and a computer attention task showed no significant change.

A 2025 laboratory study compared people with attention deficits and neurotypical people during a long visual attention task, under noise, a monaural beat and a binaural beat, while recording their EEG. The authors' conclusion is plain: binaural beats were not beneficial, neither in behaviour nor in brain activity.

A related lesson comes from neurofeedback, where children learn to change their own brain waves. In the largest double-blind trial, 142 children with ADHD improved a great deal, but those who trained on a fake signal improved just as much, and still did after two years. When a rhythm-based method is tested carefully, expectation, attention and routine explain much of the benefit.

• Binaural beats do not treat ADHD and do not replace medication, therapy or support at school or work.
• As a study background they are harmless: if a 15 Hz or 40 Hz beat helps you start a task and stay with it, use it at a low volume.
• Test it honestly: study for a week with the beat and a week with silence or plain noise, and note how much you got done each time.

Binaural beats for anxiety and meditation: alpha and theta

An alpha beat (8–14 Hz) matches the state of sitting with your eyes closed, calm but awake. It suits the end of a working day, the minutes before an important conversation, or the moment when thoughts go round in circles.

A theta beat (4–8 Hz) is slower and is associated with deep meditation and the state between waking and sleep. It helps beginners in meditation by giving attention something to rest on: you listen to the pulse instead of fighting your thoughts.

Listen sitting or lying down for 15 to 20 minutes. Breathe slowly: in for a count of four, out for a count of six.

Isochronic tones vs binaural beats

A binaural beat is made by the brain out of two tones, so it is gentle and needs headphones. An isochronic tone pulses by itself: sound, no sound. The pulse is sharper and can be heard through a speaker.

In a study by researchers in Canada and France, a sound whose pulse is in the signal itself entrained the activity of the cortex more strongly than a binaural beat. So if you can barely hear the binaural beat, or it does nothing for you, try the isochronic mode.

Binaural music or pure beats: which is better?

Most binaural tracks online are music, rain or ambient sound with the two tones mixed in underneath. A pure beat is just the two sine tones, which is what this generator plays. Which works better is one of the few questions that studies have compared directly.

The 2019 meta-analysis found that hiding the beat under white or pink noise made no difference: unmasked beats worked just as well. In the UK day-surgery trial the comparison was an identical soundtrack with and without the beats, and anxiety fell by 26.3% with them and by 11.1% without.

Other trials show how much of the effect comes from the music itself. In a trial of 141 patients having cataract surgery, music with binaural beats and the same music without them both lowered anxiety compared with headphones and no music. The difference between the two music groups was small and not significant (anxiety scores fell by 9 and by 7 points); only the beat group also showed a lower heart rate. In the South Korean insomnia trial, music with and without theta beats improved sleep equally.

The brain does lock onto music, but onto the music's own beat and note rate, roughly 1 to 8 events a second, which is set by the tempo. In one study musicians tracked it more strongly than non-musicians. No study has shown that a track labelled “alpha” or “delta” moves the brain into that band: calm music may well relax you, but the label on it is marketing.

• Choose music with beats if you enjoy it and it helps you listen longer: longer listening is one of the few things that reliably strengthens the effect.
• Choose a pure beat when you want to know exactly which frequency you are hearing, or when music distracts you while you study.
• If you want one steady pure tone without any beat, for example 432 Hz or a test tone, use the “Tone generator” page.

Are binaural beats dangerous

In studies with healthy people and with patients before surgery, no serious side effects have been described. It is a quiet sound that you listen to for as long as you like.

A few things are worth knowing.

• Volume. Hearing is harmed by loudness and duration, not by frequency. The World Health Organization considers sound of no more than 80 dB safe for up to 40 hours a week. For binaural beats a barely audible level is enough.
• Epilepsy. Rhythmic stimuli can trigger a seizure in some people with epilepsy, so talk to your doctor before listening.
• Driving. Delta, theta and alpha beats calm you down and make you sleepy. Do not listen while driving or operating machinery.
• Unpleasant sensations. If you get a headache, feel dizzy or uneasy, switch the sound off. Next time choose another frequency and a lower volume.

Sound is only one tool

Binaural beats work best when they are not alone. Sleep also depends on the light you get in the morning and in the evening, a calm nervous system also depends on breathing, and focus also depends on how you slept.

Use the generator as part of a routine: a beta or gamma beat before work, an alpha beat after it, a delta beat in bed. Keep the same time every day for a week and note how you feel; that tells you more than any single session.