Free Binaural Beats Generator
Set any carrier and beat frequency. Five brainwave presets. Live waveform. All synthesised in your browser — no download, no account.
Brainwave Band Presets
Set your carrier and beat frequency, then press Play.
Use headphones for the binaural effect.
Web Audio not supported
This generator requires Web Audio API support. Try Chrome, Firefox, Safari 14+, or Edge — or use the iOS app or Android app for the full guided experience.
Want guided sessions that adapt as you sleep?
This generator is a free tool. The BrainSync app adds unlimited sessions, sleep tracking, adaptive audio that shifts frequency as you drift off, and guided anxiety & focus programs — all without ads.
Also try the simpler BrainSync Live Player (3 fixed modes: Sleep, Calm, Focus) or the Noise Machine (pure background noise, no tones).
How Binaural Beats Work
When two slightly different pure tones are delivered separately to each ear — for example 200 Hz to the left and 206 Hz to the right — the auditory brainstem perceives a rhythmic pulsation at the difference frequency: in this case 6 Hz. This pulsation does not exist in the audio itself; it is generated entirely inside the auditory system. The phenomenon was first described by physicist Heinrich Wilhelm Dove in 1839 and has since been studied in the context of relaxation and cognition by researchers publishing through PubMed.
This generator places the left oscillator at exactly your chosen carrier frequency and the right oscillator at carrier + beat. The arithmetic: right − left = beat. Both oscillators are hard-panned (left channel: −1, right channel: +1) so each ear receives only one tone — the essential requirement for the effect.
| Band | Range | Common use | Generator preset |
|---|---|---|---|
| Delta | 0.5–4 Hz | Deep sleep, recovery | 2 Hz |
| Theta | 4–8 Hz | Meditation, REM sleep, creativity | 6 Hz |
| Alpha | 8–13 Hz | Relaxed wakefulness, calm focus | 10 Hz |
| Beta | 13–30 Hz | Active thinking, alertness | 20 Hz |
| Gamma | 30–100 Hz | High-level processing, focus | 40 Hz |
Research is ongoing. Some studies indexed on PubMed report modest effects on relaxation, sleep onset latency, and task performance. The Sleep Foundation notes binaural beats as a complementary sleep aid for some listeners. Keep expectations realistic: individual responses vary, and the science is not settled. Think of this as a pleasant auditory environment rather than a guaranteed intervention.
Frequently Asked Questions
What are binaural beats?
Binaural beats are an auditory illusion. When a slightly different frequency is delivered to each ear — say 200 Hz left and 206 Hz right — the brain perceives a rhythmic pulsation at the difference (6 Hz). The pulsation is not in the audio; it is created inside the auditory brainstem. Stereo headphones are essential because each ear must receive only one tone.
Do binaural beats really work?
Research is mixed. Some studies on PubMed suggest modest effects on relaxation, sleep onset, and certain cognitive tasks. The Sleep Foundation lists binaural beats as a potentially useful sleep aid for some people. Individual results vary significantly. Treat them as a helpful ambient environment rather than a guaranteed outcome, and use comfortable volume.
Why do I need headphones?
When you use speakers, both tones mix in the air before reaching your ears. That produces a regular acoustic beat — not a binaural one. For the brain to create the binaural perception, each ear must receive only its own frequency with no crosstalk from the other. Over-ear or in-ear stereo headphones both work; spatial or surround modes should be disabled.
Which frequency should I use for sleep?
Delta (0.5–4 Hz) is the band most associated with deep, restorative sleep. The preset here uses 2 Hz. Theta (4–8 Hz, preset 6 Hz) is associated with the hypnagogic state — the drowsy boundary between wakefulness and sleep — and may be useful if you struggle to fall asleep. Carrier frequency matters less than beat frequency for sleep; 180–220 Hz carriers are commonly used.
What is the carrier frequency and how do I choose it?
The carrier is the base tone both oscillators share. The left ear gets exactly the carrier; the right ear gets carrier + beat. The carrier itself determines the pitch of what you hear — lower carriers (100–180 Hz) feel warm and bass-like; higher ones (300–500 Hz) are brighter and more noticeable. Try 200 Hz as a starting point and adjust to taste. The beat perception is the same regardless of carrier.
What does the pink-noise bed do?
Pink noise (1/f noise) rolls off 3 dB per octave — a spectrum many people find naturally soothing. Enabling it softens the pure sine tones, masks background noise in your environment, and makes long sessions easier on the ears. It is generated live in your browser (same algorithm as the BrainSync app). Toggle it on and set the volume to your preference; the binaural effect works even with the tones nearly inaudible.
Are binaural beats safe?
For most healthy adults at comfortable listening volumes, yes. However: people with epilepsy or a history of seizures should consult a doctor first, as rhythmic stimulation may potentially trigger episodes in susceptible individuals. Pregnant people should also check with a healthcare provider. Always listen at a volume that is comfortable — do not compensate for headphone quality by increasing volume. This tool is not a medical device.
How is this different from the BrainSync app?
This web generator is a free, open-access tool designed for exploration and one-off sessions. The BrainSync app ( iOS / Android) adds unlimited sessions, sleep tracking, audio that adapts as you drift off, guided anxiety and focus programs, and offline playback — all without ads.