How to use the isochronic tones generator
- Set your sound source. Any speaker works — phone, laptop, Bluetooth, or a bedside speaker. Headphones are fine too, but optional.
- Pick a goal preset. Delta (2 Hz) for sleep, theta (6 Hz) for calm, alpha (10 Hz) for relaxed focus, beta (18 Hz) for alert focus, gamma (40 Hz) for peak concentration.
- Shape the pulse. "Smooth" is gentler for sleep; "Sharp" is more pronounced for focus. Add brown noise to soften and mask distractions.
- Press play. The sound fades in gently. Let the steady pulse do the work.
What are isochronic tones?
An isochronic tone is a single tone switched on and off at a steady rate — a clean, evenly spaced pulse. Because the rhythm is carried by one tone rather than the difference between two, it survives on a loudspeaker and needs no stereo separation. That makes it the headphone-free way to entrain: ideal for a bedside speaker, the car, or shared spaces. Read the full evidence-aware explainer →
Prefer headphones? Try the free binaural beats generator — two tones, one per ear, for a softer phantom beat.
Free generator vs. the Entrain app
This browser tool is a real taste of Entrain. The app adds 20 tuned presets, your own saved frequencies, brown/pink/rain/ocean ambient layers, a sleep timer up to 8 hours, background and lock-screen playback, session history, and native apps for iPhone, iPad, Apple Watch, and Mac — all fully offline. See plans →
Frequently asked
Do isochronic tones need headphones?
No. Isochronic tones are a single tone pulsed on and off, so the rhythm survives on any speaker — phone, laptop, Bluetooth, AirPlay, or car audio. Headphones are optional. This is why they're the headphone-free alternative to binaural beats.
Is this isochronic tones generator free?
Yes — it runs entirely in your browser with no account and no download. Sessions are capped at 30 minutes. The Entrain app removes the cap and adds presets, sleep timers, more ambient layers, background playback, and Apple Watch.
What is the brown noise layer for?
Brown noise is a deep, soft static that masks background distractions and rounds out the pulsing tone, which many people find more soothing for sleep and focus. Slide it up to taste or down to zero for a pure tone.
Smooth or sharp pulse — which should I use?
Smooth (a sine pulse) is gentler and better for winding down and sleep. Sharp (a square pulse) has a more defined on/off edge that some people find better for alert focus. Try both.