Binaural Beats Generator
This is a free binaural beats generator that plays two pure tones, one per ear, synthesized live in your browser. Pick a preset for focus, relaxation, or sleep, or open Advanced Tuning to dial in an exact base and beat frequency yourself — nothing downloads, nothing uploads, and nothing plays until you tap something.
What Are Binaural Beats and How Do They Work?
A binaural beat isn't a single recorded sound — it's an effect your brain creates. This generator plays one steady tone in your left ear and a second tone, slightly higher or lower in pitch, in your right ear. Your brain perceives the small difference between the two as a slow pulsing "beat," at a rate equal to that frequency gap. Play the same two tones through one speaker instead of headphones and the effect disappears, because both ears hear both tones mixed together — this is why headphones are required.
Focus, Relax, or Sleep — Choosing a Preset
Three presets on the main screen map to brainwave ranges commonly associated with different mental states: Focus uses a 40Hz beat in the Gamma range, linked to alertness and concentration; Relax uses a 10Hz Alpha-range beat, a calm, relaxed-but-awake state; and Sleep uses a slow 2Hz Delta-range beat associated with deep sleep. Tapping any preset starts playback immediately at that beat frequency over a fixed 200Hz base tone.
Custom Tuning: Base Frequency and Beat Frequency
Open Advanced Tuning to move past the presets entirely. The Base Frequency slider sets the underlying tone from 100Hz to 1000Hz, and the Beat Frequency slider sets the gap between your two ears from 0.1Hz to 40Hz in 0.1Hz steps. Both sliders apply live, including while a beat is already playing, so you can sweep through frequencies until one feels right rather than restarting playback each time.
Binaural Beats Frequency Chart (Delta to Gamma)
Beat frequencies are grouped into bands that roughly track natural brainwave ranges: Delta (0.5–4Hz) for deep, dreamless sleep; Theta (4–8Hz) for light sleep, deep relaxation, or meditation; Alpha (8–13Hz) for a calm, relaxed-but-awake state; Beta (13–30Hz) for normal waking alertness; and Gamma (30–40Hz+) for peak focus and concentration. The Advanced Tuning slider covers the full 0.1–40Hz range if you want to explore beyond the three presets.
Do Binaural Beats Actually Work?
The honest answer is: the evidence is mixed. Some small studies report short-term shifts in mood, relaxation, or attention while listening, but results are inconsistent and binaural beats are not a medically proven treatment for anything. Most people who use them do so as a simple listening aid alongside quiet time, work, or winding down for sleep — worth trying, not a guarantee.
Frequently Asked Questions
Do binaural beats actually work?
Some research links binaural beats to small, short-term shifts in mood or relaxation, but the evidence is mixed and nowhere near a guarantee — treat them as a listening aid to try, not a proven fix. Many people find a steady beat under focus, relaxation, or sleep sounds genuinely helpful regardless of the underlying mechanism.
Do you need headphones for binaural beats to work?
Yes. Binaural beats rely on each ear hearing a slightly different tone, and only headphones or earbuds keep those two tones fully separated. Playing through a single speaker lets both tones reach both ears and mix in the air, so the beat effect doesn't form.
What frequency is best for focus?
A beat frequency around 40Hz, in the Gamma range, is the one most associated with alertness and concentration — it's the basis for this generator's Focus preset. You can fine-tune it further with Advanced Tuning if 40Hz doesn't feel right for you.
What's the best frequency for sleep?
Slow Delta-range beats, around 1–4Hz, are the frequencies most associated with deep sleep — this generator's Sleep preset uses 2Hz. Lower beat frequencies in general trend toward calmer, more restful states than the faster Gamma range used for focus.
Binaural beats vs. isochronic tones — what's the difference?
Binaural beats play two slightly different steady tones, one per ear, and the beat is an effect your brain perceives from the difference — it requires headphones. Isochronic tones are a single tone pulsed on and off at the target rate, so they work through open speakers too, but they're a different technique from what this generator produces.
Are binaural beats safe?
For most people, listening to binaural beats at a comfortable volume is considered safe — it's just sound. People with epilepsy or a history of seizures should be more cautious with any rhythmic audio or visual stimulation and may want to check with a doctor first. As with any headphone listening, keep the volume moderate.
How are binaural beats made?
Two pure sine-wave tones are generated at slightly different frequencies — a base tone and that same tone shifted up and down by half the target beat frequency — then sent one to each ear. This generator synthesizes both tones live using the Web Audio API, so nothing is downloaded or streamed.
