Background sound
White, pink & brown noise
Choose a background sound, then adjust it to your preference. Generated on your device, with no stream or account. Start at a low volume.
Ready — press Play to start audio.
Browsers require a press to start audio. Background/lock-screen playback may be interrupted; the status follows the real audio context. This is background sound, with no promised sleep or medical result.
The timer starts on Play and keeps counting during pauses. Cancel removes the planned fade. The browser can suspend audio in the background; return to this page to verify its state.
On-device presets
Up to five presets, saved only on this browser. Restore checks every parameter and never restores playback or an old deadline.
Method and sources
- Method / source
- White noise uses uniform random samples; pink uses a multi-stage filter to approximate 1/f power; brown uses a leaky integrator for a lower-frequency emphasis. An eight-second generated buffer has a50ms crossfade seam. A low-pass filter controls brightness and AudioParam envelopes provide fades and timed silence.
- Who it suits
- People who want an adjustable background sound.
- Who it does not suit
- Medical assessment or prescribed sound treatment; no therapy or outcome is promised.
- Limitations
- Preferences differ. Browsers may interrupt background or lock-screen audio. Volume percentage is not a sound-pressure or safe-duration measurement.
- Explanation updated
- Technical explanation updated:2026-11-13
Primary sources: MDN: Web Audio API · MDN: autoplay restrictions
Frequently asked
How do the three sounds differ?
White noise has relatively even power across frequencies and sounds brighter. Pink emphasizes lower frequencies; brown is lower still. These are program-generated approximations, not a radio stream or audio library. Preference varies; there is no sleep or treatment outcome promise.
Why must I press Play?
Mainstream browsers require a user gesture to start audio. Play creates or resumes the AudioContext. System interruption or automatic suspension is shown as interrupted, requiring another press, rather than claiming sound is still playing.
How do the timer and cancel work?
Choose15,30 or60 minutes. It starts on playback and keeps counting during pauses. A fade envelope is scheduled on the audio clock; canceling removes the scheduled fade. A timer set before playback waits for the next Play.
Will it work in the background or on the lock screen?
The browser and operating system decide; it cannot be guaranteed. The UI follows the real audio-context state and checks it again on return. An expired timer mutes before any resume. Media controls are available where the browser supports them.
What do presets save?
Only when you save: sound, volume, filter frequency, fade lengths and timer choice, locally in this browser, up to five presets. Restored values are range-checked. Playback state and absolute stop times are not saved or synced. Start quietly and stop if uncomfortable.