AnyTool
Your files never leave your device. All processing happens locally in your browser.

How do I play white, pink or brown noise online for focus or sleep?

Open AnyTool White Noise Generator, pick a noise colour — white, pink, brown, blue or violet — or an ambient soundscape like rain, ocean waves, wind, fan or stream, then press Play. The sound is synthesized live in your browser with the Web Audio API (no audio files), so it loops seamlessly and starts and stops without clicks. Adjust the volume, use the tone slider to make it warmer or brighter, and set a 5–60 minute sleep timer that fades out gently before stopping. Keep the volume moderate, especially overnight.

  • Five noise colours: white (flat), pink (−3 dB/oct), brown (−6 dB/oct), blue and violet
  • Ambient soundscapes: rain, ocean waves, wind, fan and stream (filtered noise + slow LFO)
  • Tone slider tilts the sound warmer/darker or brighter; volume with smooth ramps
  • Sleep timer (5/10/15/30/60 min) fades out gently, then stops
  • Synthesized 100% in your browser — no audio files, no upload, works offline

What is

White Noise (and noise colours)

White noise is a sound with equal energy at every frequency, which is why it sounds like a flat, steady hiss; it is often used to mask distractions for focus or sleep. Other “colours” shift that balance: pink noise rolls off at about −3 dB per octave for a deeper, more natural sound like steady rain; brown (red) noise drops −6 dB per octave for a low rumble like a waterfall or distant surf; blue and violet noise tilt the opposite way, emphasising high frequencies. A web noise generator synthesizes these in the browser with the Web Audio API, with no files to download.

Generators

Related terms

Pink noiseBrown noiseAmbient soundSleep timerWeb Audio API

Frequently Asked Questions

White noise has equal energy at every frequency (a flat hiss). Pink noise rolls off the highs for a balanced, rain-like sound. Brown noise rolls off more, giving a deep rumble.

All three are broadband noise; they differ in how energy is spread across frequencies. White noise has equal power per hertz, so it sounds bright and hissy, like an untuned radio. Pink noise reduces high frequencies by about 3 dB per octave, making it sound fuller and more natural — many people compare it to steady rainfall and find it less harsh than white noise. Brown (or red) noise rolls off by about 6 dB per octave, pushing energy into the bass for a deep rumble like a waterfall or distant surf. There is also blue and violet noise, which tilt toward the highs for a crisp, airy sound. Which is “best” is mostly personal preference: white noise masks the widest range of distractions, while pink and brown are often felt to be more soothing for sleep.

No. Every sound is generated mathematically in your browser with the Web Audio API and looped, so there are no audio files and nothing is uploaded or streamed.

The generator fills a short audio buffer with the right algorithm and loops it seamlessly: white noise is uniform random samples, pink noise uses Paul Kellet’s refined filter that approximates a −3 dB/octave slope, and brown noise is a leaky integration of white noise for a −6 dB/octave slope; blue and violet are made by differentiating white noise. The ambient soundscapes are that base noise shaped with band-pass filters, plus a slow amplitude oscillator that makes the ocean and wind swell and recede. Because it is all synthesized locally, there are no files to download or stream, no CDN, and the tool works offline once the page is cached.

Yes. Pick 5, 10, 15, 30 or 60 minutes and the sound gradually fades to silence over the last few seconds before it stops — no abrupt cut-off.

When you set a sleep timer, a countdown runs while the noise plays. In the final seconds the volume is ramped smoothly down to silence and then the audio is stopped and the audio context is suspended, so you get a gentle fade rather than a sudden silence that might wake you. You can change the duration at any time, and pressing Stop fades out and tears everything down cleanly too. All volume changes ramp gradually, so switching colours, ambiences or volume never produces a click or pop.

No. It can help mask sounds and some people find it relaxing, but it is not a medical treatment. See a doctor or audiologist for persistent tinnitus or sleep problems.

Noise and ambient sound can help mask distracting environmental sounds and many people find them calming for focus or falling asleep, but the evidence is mixed and the effect is largely down to personal preference rather than proven science. This tool is designed for focus and relaxation, not as a medical device, and it cannot diagnose or treat tinnitus, insomnia or any condition. Keep the volume moderate — prolonged loud sound can damage hearing, and for babies and children sleep experts recommend keeping noise machines quiet and away from the bed. If you are dealing with ongoing tinnitus or sleep difficulties, please consult a qualified professional.

Detailed Explanation

Methodology

How the Noise Is Generated and Played

AnyTool White Noise Generator synthesizes every sound procedurally with the native Web Audio API — there are no audio files to download or stream. A few seconds of the chosen noise colour is written into an AudioBuffer using the correct algorithm and looped seamlessly with an AudioBufferSourceNode: white noise is uniform random samples (a flat spectrum), pink noise uses Paul Kellet’s refined seven-term filter to approximate a −3 dB/octave slope, brown (red) noise is a leaky integration of white noise for a −6 dB/octave slope, and blue and violet noise are produced by differentiating white noise to tilt energy toward the highs. The looping source feeds a high-pass and a low-pass BiquadFilter (for tone shaping and ambient bandpass effects), then a GainNode, then an AnalyserNode that drives a live spectrum, then the destination. Gain is always moved with linearRampToValueAtTime so starting, stopping, switching colours and the sleep-timer fade are click-free, and the AudioContext is created lazily on the first gesture (autoplay policy), suspended when idle and closed on unmount.

  • BufferSource(loop) → highpass → lowpass → GainNode → AnalyserNode → destination, all native Web Audio
  • White = uniform random; pink = Paul Kellet refined filter (−3 dB/oct); brown = leaky-integrated white (−6 dB/oct)
  • Blue and violet are made by differentiating white noise (+3 / +6 dB/oct tilt)
  • Gain ramped with linearRampToValueAtTime — no clicks when switching or fading
  • Synthesized locally: no audio files, no CDN, works offline; mic never used
How It Works

Ambient Soundscapes, Tone Tilt and Sleep Timer

Beyond the five plain colours, five ambient soundscapes are built by re-shaping a base noise colour with the two biquad filters: rain is band-limited pink noise, ocean waves are low-passed brown noise, wind is a narrow low-passed brown band, fan is a steady band-passed pink drone, and stream is bright high-passed white noise. For the ocean, wind and stream presets a slow sine LFO modulates the master gain so the sound swells and recedes like real surf or gusts rather than sitting perfectly flat. A tone slider tilts the whole spectrum, multiplicatively lowering the low-pass corner to sound warmer and darker or raising both corners to sound brighter, updated by re-targeting the filters without rebuilding the graph. A sleep timer of 5, 10, 15, 30 or 60 minutes runs a countdown and, in the final few seconds, ramps the gain smoothly to silence before stopping and suspending the context, so the sound fades out gently instead of cutting off abruptly.

  • Rain, ocean waves, wind, fan and stream = a base colour shaped by high-pass / low-pass biquads
  • Ocean and wind use a slow gain LFO so the sound swells and recedes naturally
  • Tone slider re-targets the filter corners for a warmer or brighter sound — no glitch
  • Sleep timer (5/10/15/30/60 min) fades to silence over the last seconds, then stops
  • A live spectrum is drawn from a real AnalyserNode reading the generated signal
Limitations

Privacy and an Honest Note on Use

Because all sound is synthesized in the browser, nothing is uploaded, recorded or stored, the microphone is never accessed, and the generator works offline once cached; even the spectrum bars are computed locally from the noise you are generating. Honestly, while many people find noise and ambient sound helpful for masking distractions, focusing or relaxing, the evidence is mixed and which colour works best is largely personal preference rather than settled science. This is a focus-and-relaxation tool, not a medical treatment — it cannot diagnose or treat tinnitus, insomnia or any condition. Keep the volume moderate, especially if it plays overnight, since prolonged loud sound can harm hearing, and sleep experts recommend keeping noise machines quiet and away from the bed for babies and children; anyone with persistent tinnitus or sleep problems should consult a doctor or audiologist.

White Noise Generator: in-browser (AnyTool) vs typical online noise sites
CapabilityAnyToolTypical online noise sites
Audio sourceSynthesized live (procedural, looped buffer)Often streams/loops audio files from a CDN
Noise coloursWhite, pink, brown, blue, violetFrequently white + pink + brown only
Ambient soundscapesRain, ocean, wind, fan, stream (filtered noise)Sometimes sampled loops
Tone controlWarmer/brighter tilt via biquad filtersRarely offered
Sleep timer5–60 min with a gentle fade-outOften none or a hard cut-off
Click-free changesGain ramped on every changeOften abrupt switches
PrivacyNo upload, no CDN, offline-capableMay stream assets / track

AnyTool generates every noise colour and ambience locally with the native Web Audio API and uploads nothing.