For open-plan offices, coworking spaces and shared rooms
A flat layer of sound that covers conversation and movement, so you are not spending attention on reacting to interruptions. Everything is generated in your browser. Nothing is uploaded, nothing is recorded, no account.
Being straight with you: this will not make you smarter or faster. It covers noise. That is the whole claim, and it is the one the research actually supports. See the evidence below.
Pick a sound above, then press start. Browsers require a click before audio can play — that is a browser rule, not a nag.
All six beds are matched to the same perceived loudness, so switching never jolts your ears. Keep it low — long exposure at high volume is tiring and can cause headaches.
A fade-out over the last 20 seconds, so it never wakes you abruptly.
Most products in this category promise more than the evidence supports. Here is the short version, with the numbers.
A Bayesian meta-analysis of 65 studies found background noise, speech and music all have a small but reliably harmful effect on reading comprehension. Lyrics were the worst.
So: if your work involves reading, try the sound on for the writing and thinking, and turn it down or off for the reading.
Beyrer et al., Psychological Science (2018)A 2024 systematic review screened 753 records and kept 13. Twelve studied white noise, one studied pink, and zero studied brown noise. It is the internet's favourite and the literature's blank spot.
So: treat brown noise as a sound preference, not a performance intervention. Nothing says it is worse — nothing has tested it either.
Nigg et al., JAACAP (2024)In that same review, white and pink noise gave a small but real benefit for people with ADHD or high ADHD symptoms (g = 0.249). For everyone else the same noise measurably impaired performance.
So: if you have ADHD, pink is the one to try. If you do not, treat it as masking only and keep it low.
Nigg et al., JAACAP (2024)On a sustained-attention test, people’s own chosen music increased their reported focus and cut down mind-wandering — but their reaction times did not improve at all.
So: the benefit is real, and it is in your experience rather than your output. Worth having. Not worth overselling.
Psychological Research (2021)In a controlled stress test, rippling water produced the lowest cortisol of any condition — lower than a piece of calming classical music.
So: that is why Stream is here and not buried. It is the best-evidenced calm sound on this page.
PLOS ONE (2013)Plenty of apps say brown noise matches your brain’s 1/f rhythm. Brain activity does scale as 1/f — that part is solid. But that describes electrical recordings of neurons, not sound in a room. A −6 dB/octave sound does not impose −6 dB/octave on your cortex.
So: pleasant mechanism, no supporting study. Enjoy the sound on its own terms.
No. Every sound is generated in your browser from arithmetic, using your device’s CPU. There is no upload, no microphone access, no analytics on this page, and no account. You can go offline after the page loads.
Because it is the sound people ask for by name, and the first thing that deserves is an accurate label. If you have read that it is scientifically proven to improve focus, that claim is not in the literature.
Noise-like beds (brown, pink, white, fan) are the best at covering speech, because speech sits in a similar frequency range. Water and rain are the least fatiguing over a long session. Start with the one described closest to a real sound you like — fan if you like a fan, rain if you like rain.
No audio is. Keep it at a level where you can hear someone speak to you from a metre away. Long exposure at high volume causes fatigue and, for some people, headaches. If you have tinnitus, be conservative.
Yes, and it is the main use case. On iOS, tap Start inside the same gesture that first creates the audio engine — iOS only permits audio after a real tap. The page is built mobile-first.
Because music is a worse masker than a flat bed, and because music hurts comprehension (see the first card). A generator that plays a fixed repetitive bed is doing a different job: it covers, it does not distract.