Binaural beats generator
Each ear gets its own sine tone, and the two differ by a few hertz. In your head this creates a slow beat – the binaural beat. It only works with headphones.
How it is calculated
How it works
- Put on headphones and use the headphone test to check left and right.
- Choose the carrier frequency (the middle pitch) and the difference between the ears.
- Optionally set a duration – at the end the tone fades out gently.
- Press “Play” and raise the volume slowly.
Example: carrier 200 Hz and difference 6 Hz give 197 Hz on the left and 203 Hz on the right.
What is a binaural beat?
When each ear hears a slightly different tone separately, you perceive a beat at the difference frequency – described by Gerald Oster in Scientific American in 1973. According to the review by Ingendoh and colleagues (PLOS ONE 2023), the effect appears for differences of roughly 1 to 30 Hz, only when both tones are at most about 1000 Hz, and it is clearest around 400 Hz. The tool therefore limits its settings to these ranges.
What the research says
It is often claimed that binaural beats “entrain” brainwaves to their frequency. The systematic review mentioned above analysed 14 EEG studies on this: five reported results in line with the idea, eight contradicted it and one was mixed. The authors describe the evidence as inconsistent overall. This tool therefore makes no promises about sleep, focus or mood – it generates the tones, nothing more.
Notes
Do not use it while driving or doing anything that needs your attention. The WHO gives as a guide that at an average of 80 dB you can listen safely for up to 40 hours a week – quieter is better. If you have health complaints, seek medical advice rather than relying on tones.
Frequently asked questions
Do I really need headphones?
Yes. The effect only appears when each ear hears its own tone separately. Through speakers the two tones already mix in the air.
Do binaural beats help with sleep or studying?
That is not established. A systematic review (PLOS ONE 2023) found inconsistent results on brainwave effects, so this tool makes no claims about effects.
Which carrier frequency makes sense?
Both tones must stay below about 1000 Hz, and the effect is clearest around 400 Hz. Lower carriers are a matter of taste.
How large can the difference be?
About 1 to 30 Hz. With larger gaps you hear two separate tones instead of a beat, so the tool limits the difference to 30 Hz.
Is anything stored?
Only your settings, so you find them again and can share them as a link. The tones are generated live in the browser.
Sources and legal basis
- Ingendoh RM, Posny ES, Heine A: Binaural beats to entrain the brain? A systematic review. PLOS ONE 2023;18(5):e0286023
- Oster G: Auditory Beats in the Brain. Scientific American 1973;229(4):94–102
- MDN Web Docs – ChannelMergerNode (Web Audio API)
- WHO – Deafness and hearing loss: Safe listening
As of:
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