Brainwave frequencies explained
Last updated June 2026
Your brain hums with electrical activity, and that activity rises and falls in rhythms measured in cycles per second — hertz. Group those rhythms by speed and you get five bands, each tied to a characteristic state of mind, from the deep slow sway of sleep to the fast flicker of peak focus.
What EEG frequency bands are
An electroencephalogram (EEG) records the summed electrical activity of millions of neurons firing in loose synchrony. That activity oscillates, and the speed of the oscillation — its frequency — tracks closely with what the brain is doing. Slow rhythms dominate during sleep; faster rhythms dominate during alert thinking.
Researchers split this continuum into five conventional bands: delta, theta, alpha, beta, and gamma. The boundaries are conventions, not hard walls, and they vary a little between sources — but the broad picture is consistent and useful. The premise behind brainwave entrainment is that rhythmic sound at a chosen frequency may help nudge the brain's dominant rhythm toward that band.
The five bands
Tap any band to read it in depth.
Delta — 0.5–4 Hz
The slowest rhythms, dominant during deep, dreamless NREM sleep. Delta is the band of physical restoration: it's when the body does much of its repair. This is the target for genuine sleep, not just winding down.
Theta — 4–8 Hz
The drifting, twilight band — present in deep meditation, calm, anxiety relief, and the hazy state between waking and sleep. A good choice for relaxation, mindfulness, and easing toward bed.
Alpha — 8–13 Hz
The bridge between relaxation and alertness. Alpha rises when you're calm but awake — relaxed concentration, a sense of flow, eyes-closed quiet. A popular target for unhurried focus and stress relief.
Beta — 13–30 Hz
The rhythm of alert, engaged thinking — active problem-solving, concentration, and busy mental work. Reach for beta when you want to be switched on and productive rather than calm.
Gamma — 30–100 Hz
The fastest rhythms, linked to peak focus, moments of insight, fast learning, and the brain binding information together across regions. The most demanding band, and the one with the most still to learn about it.
How to choose a target frequency by goal
The simplest way to pick is to start from what you want to feel, then choose the matching band:
- Sleep → delta (slow, 0.5–4 Hz).
- Calm & meditation → theta (4–8 Hz).
- Relaxed focus & flow → alpha (8–13 Hz).
- Alert, active focus → beta (13–30 Hz).
- Peak focus & insight → gamma (30 Hz and up).
A note on the evidence: these mappings are well-established conventions for what each band correlates with, but entrainment — actively shifting your state with sound — is promising rather than proven, and individual responses vary. Treat target frequencies as a sensible starting point to experiment from, not a precise dial for your mood.
The 7.83 Hz "Schumann resonance" preset
You'll often see 7.83 Hz singled out. It's the fundamental Schumann resonance — a natural electromagnetic frequency of the cavity between Earth's surface and the ionosphere. It happens to fall in the upper theta band, which is why 7.83 Hz has become a popular preset for grounding and meditation. The link to relaxation is more popular lore than established science, but plenty of people enjoy it as a theta starting point — and Entrain makes it easy to try.
Choosing frequencies in Entrain
Entrain includes 20 presets across Sleep, Relax, Focus, and Energy, spanning roughly 0.25–40 Hz, so you can pick a goal and let the app set a sensible band. Prefer to be precise? Dial in any target frequency by hand — for either binaural beats (headphones) or isochronic tones (any speaker) — and let a gentle fade-in and sleep timer handle the rest.
Frequently asked
What are the five brainwave frequency bands?
Delta (0.5–4 Hz) for deep, dreamless sleep and physical repair; theta (4–8 Hz) for meditation, calm, and pre-sleep drifting; alpha (8–13 Hz) for relaxed concentration and flow; beta (13–30 Hz) for alert, active thinking and problem-solving; and gamma (30–100 Hz) for peak focus, insight, and fast learning. These ranges are conventions and the exact boundaries vary slightly between sources.
What frequency should I target for sleep?
For deep sleep, target the slow delta band (about 0.5–4 Hz). To wind down and drift off, the theta band (4–8 Hz) is a good pre-sleep choice. Pair a slow frequency with a sleep timer and, if you like, a brown-noise layer.
What is the 7.83 Hz Schumann resonance?
7.83 Hz is the fundamental Schumann resonance — a natural electromagnetic frequency of the space between Earth's surface and the ionosphere. It happens to sit in the theta band, which is why 7.83 Hz is a popular preset for grounding and meditation. The association with relaxation is popular and anecdotal rather than firmly established science.
Can I choose any frequency in Entrain?
Yes. Entrain ships 20 presets across Sleep, Relax, Focus, and Energy spanning roughly 0.25–40 Hz, and you can also dial in any target frequency by hand for either binaural beats or isochronic tones.