White, Pink, and Brown Noise for Focus

What the colours actually are

The colours describe the sound spectrum, not a medical property. White noise carries equal energy at every frequency and sounds like a hiss or static. Pink noise has less energy as the frequency rises, so it sounds softer and lower — more like steady rain. Brown noise (also called red noise) falls off faster still, a deep rumble like a waterfall heard from a distance. Any free noise app or video can produce all three; no special device is needed, and the colour names tell you nothing about whether the sound will help you work.

What the evidence shows

The best summary is a 2024 systematic review and meta-analysis in the Journal of the American Academy of Child & Adolescent Psychiatry. It pooled 13 controlled studies (335 participants — children and college-age young adults with ADHD or elevated attention problems) and found that white or pink noise improved task performance by a small amount, about a quarter of a standard deviation.¹ The same review found the other side of the coin: participants without ADHD did slightly worse with the same noise playing.¹

The pattern is not new. An earlier study found the same split: children with ADHD remembered more on a memory task with white noise playing, while children without ADHD remembered less.² And volume changes the result: in a 2022 study of 39 neurotypical graduate students, quiet white noise at 45 dB improved sustained attention and lowered stress, while louder noise at 65 dB improved working memory but raised stress — louder is not better.³

One popular pink-noise claim needs a correction. A 2017 study did find that pink-noise pulses played during sleep improved deep-sleep waves and next-day memory in older adults.⁴ But that was pulses timed to slow brain waves during the night — a sleep study, not a focus study. It says nothing about playing pink noise at your desk while you work, and the claim does not transfer.

Brown noise: the gap

Brown noise is the most talked-about colour and the least studied. The 2024 meta-analysis searched for it and found no studies to pool — its authors say so plainly.¹ Every claim that brown noise helps focus borrows from white- or pink-noise data and assumes the benefit transfers. That is an assumption, not a finding: the colours differ in sound, and nobody has measured whether the difference matters for attention.

None of this means brown noise does nothing. It means nobody has tested it under controlled conditions. If you like the sound — many people find the low rumble the least irritating of the three — that is a perfectly good reason to use it. Just do not mistake comfort for evidence, and do not pay anyone for a special brown-noise track: the free ones are the same sound.

How to run your own one-week test

• Pick one colour. White has the most evidence; brown is the most comfortable for many listeners. Either is fine for a test.
• Keep it low. About as loud as a quiet room. If you have to raise your voice to talk over it, turn it down — the study that found a benefit used 45 dB, and louder raised stress.³
• Same task, same time. One kind of work, one slot in the day, one week with the noise on.
• Track two numbers. Tasks started and tasks finished each day — the same measures that matter for any focus routine.
• Compare against a quiet week. One week with noise, one week without, same task, same time. If the notes show nothing, the noise is not doing anything for you.
• Do not stack variables. One colour, one volume, one week — then judge. Changing the sound, the volume, and the task at once tells you nothing.

Noise vs music vs guided audio

Noise and music are not the same tool. A systematic review of 95 articles found that background music generally harms memory and language tasks, that lyrics are worse than instrumental music, and that the harm grows with task difficulty.⁵ Noise has no lyrics and no melody to follow, which is why it is the steadier choice for reading and writing. If music helps you work, it is probably the routine and the mood, not the sound — test it the same way, one week on and one week off.

Guided audio is a different tool again: a voice structuring your attention, rather than sound masking the room. The Genius Switch bundles guided sessions with background tones in one program. Noise can sit underneath a guided session, but the two do different jobs — masking versus structure — and only your own notes will tell you which one your workday is missing.

Before you listen

• Keep the volume moderate. Louder is not better, and long listening at high volume is a hearing risk.
• Never while driving or doing anything that needs your full attention.
• Tinnitus or hearing concerns? Ask a doctor or audiologist before long daily listening at volume.
• It is a masking aid, not a treatment for attention, anxiety, or sleep problems.