Noise Generator
Sleep sound machine with white, pink, brown noise, rain, ocean waves & nature sounds. Sleep timer with fade-out, binaural beats for deep sleep & focus. Free ambient noise generator
White noise, pink noise, brown noise — they sound similar but have different spectral content and different effects on attention and sleep. White noise has equal power per Hz (sounds hissy); pink noise has equal power per octave (sounds like rain on leaves); brown noise has more bass (sounds like ocean or distant traffic). This generator plays each, plus nature sounds, lets you mix them, and sets a fade-out timer for sleep use.
The colors of noise
- White noise — flat spectrum, equal power at every frequency. Sounds hissy; mask high-frequency content well (typing, voices). Common for tinnitus relief.
- Pink noise — power proportional to 1/f. Equal power per octave. Sounds like steady rain or wind. Most universally pleasant; some sleep studies suggest pink noise improves deep-sleep duration.
- Brown / Red noise — power proportional to 1/f². Bass-heavy; sounds like waterfall or distant traffic. Best for blocking deep voices and rumbles.
- Blue noise — power proportional to f. Treble-heavy. Useful in dithering, less common for ambient listening.
- Violet noise — power proportional to f². Even more treble-heavy. Niche; can help with low-frequency tinnitus.
- Grey noise — perceptually flat (compensated for the human ear's frequency response). Subjectively "balanced" to listeners.
- Natural sounds — rain, ocean, forest, fireplace, fan. Acoustically these are mostly pink-noise-like with overlaid transients. Many users prefer them over synthetic noise.
- Binaural beats — two slightly-different tones in each ear; the brain perceives the difference frequency. Claims of attention/relaxation effects exist; evidence is mixed.
Working example: blocking office distraction
Input
You work in an open office. Coworkers talk; you cannot focus.
Output
Diagnosis:
Distracting noise: human voices (200-4000 Hz range, conversational speech)
Sounds you want to mask: voices, occasional kitchen noise (1000-8000 Hz)
Sounds you want to preserve: emergency alarms, your name being called
Options:
- Pink noise at 50-60 dB (moderate volume)
Pros: masks conversational speech; sounds natural; can listen for hours.
Cons: still hear most details if someone is right next to you.
- Brown noise + light rain blend
Pros: bass-heavy masking; thicker barrier against voices.
Cons: can muffle alarms too. If using in shared safety contexts, lower volume.
- Music with lyrics: NO. Lyrics compete for verbal-processing brain bandwidth.
- Music without lyrics (classical, lo-fi): yes, but less effective masking than noise.
Typical recommendation: pink noise at moderate volume + occasional break. The brain
adapts to constant background; after ~20 minutes you stop noticing the noise itself.50-60 dB is roughly conversational volume. At 70+ dB the noise itself becomes fatiguing and may damage hearing over hours. Test with a phone's sound-level meter before extended use; 65 dB is a safe upper bound.
Use cases and what works for each
- Sleeping — pink or brown noise at low volume (40-50 dB). Use a sleep timer to fade out after 30-60 minutes; sleeping in noise all night is fine but unnecessary once you are asleep.
- Focus / studying — pink noise. White noise can fatigue; brown noise can lull. Pink has the best fatigue-to-mask ratio for most people.
- Tinnitus relief — depends on the tinnitus pitch. High-frequency tinnitus is masked by white/pink; low-frequency by brown. Match volume to just-barely-mask the tinnitus, not to drown it out.
- Baby sleep — pink or brown noise around 50-65 dB. Mimics womb sounds. Use until baby is asleep, then fade out (loud noise all night is not recommended even for babies).
- Travel — earplugs + brown noise via earbuds. Blocks engine noise, conversations, footsteps.
- Migraine / sound sensitivity — minimal noise or none. Some people find brown noise soothing during migraine onset; others find any noise unbearable.
Acoustic safety
- Hearing-damage threshold: ~85 dB over 8 hours; ~88 dB over 4 hours; doubling intensity halves the safe duration.
- Earbuds at "comfortable" volume often exceed 70-80 dB. Long sessions cause cumulative damage.
- Bone-conduction headphones bypass the eardrum but still transmit through the inner ear; the same exposure limits apply.
- For sleep, prefer external speakers over in-ear earbuds — earbuds for 8 hours can cause skin irritation and earwax buildup.
- Children and especially infants: keep below 50 dB. Hearing develops through age 5 and is more susceptible to damage than adult hearing.
When to reach for this tool
- You are working in a noisy environment and want to mask the distractions.
- You are trying to fall asleep in an unfamiliar room (hotel, travel) where the silence or noise pattern differs from home.
- You are caring for a baby and want a sound-machine alternative without buying hardware.
- You have tinnitus and want to test which noise color masks your specific frequency best.
What this tool will not do
- It will not cure tinnitus. Noise can mask the sensation while playing; the underlying condition persists. For chronic tinnitus, see an audiologist.
- It will not replace ear protection. For loud environments (concerts, machinery), use proper ear protection. Masking does not reduce sound exposure to the inner ear.
- It will not work without a speaker / headphones playing. If your browser tab is muted or paused, no noise plays.
Frequently asked questions
Is white noise actually the best for sleep?
Probably not. Pink or brown noise is more pleasant for most people and may have slightly better deep-sleep effects (some small studies suggest, but evidence is mixed). White noise works fine; pink noise works at least as well for most users. Try both for a week each.
Can white noise damage babies' hearing?
At high volumes, yes — same exposure rules as adults. Keep below 50 dB. Position the sound machine across the room, not in the crib. Use only as long as needed to settle for sleep; long-term continuous loud noise is associated with auditory development concerns.
What is "brown noise"?
"Brown" refers to Brownian motion (random walk) — power decreases at 1/f² with frequency. So brown noise has much more bass than white or pink. Subjectively: deeper rumble. Some users find it more relaxing; some find it heavy.
Do binaural beats actually do anything?
Mixed evidence. Small studies suggest mild attention/relaxation effects for some users; large-scale evidence is weak. The effect is unlikely to be dramatic. Try them; if they help, use them; do not expect miracles.
Is rain or nature sounds better than synthetic noise?
For most people, yes — both subjectively and in adherence (people stick with sounds they enjoy). Acoustically, rain and ocean are mostly pink-noise-like, so the masking effect is similar. The transients (a clap of thunder) can occasionally wake light sleepers.
Can I generate noise files offline?
Yes — the audio is synthesized in your browser via Web Audio API. For offline use, record the playback or download a sample file generated by a different tool. Synthesized noise is technically the same regardless of source.
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Last updated · E-Utils editorial team