White Noise for Sleep

When it helps

• Unpredictable noise — city traffic, thin walls, a partner who moves, a snorer in the next room, hotel corridors.
• Shift workers sleeping during the day, when the environment is noisy by default.
• New environments — see sleeping in new places.
• Tinnitus, where a low-level background can reduce the contrast with the perceived sound.

When it does little

• A room that is already quiet — there is nothing to mask.
• When the problem is not noise: rumination, pain, temperature, or a diluted sleep drive will not respond. See why can't I sleep.

Which sound

• White noise — all frequencies equally; sounds like a fan or radio static. Effective masking, but some find it harsh.
• Pink noise — more energy at lower frequencies, closer to rainfall. Many people find it more pleasant and it masks low-frequency traffic well.
• Brown noise — deeper still, like distant surf. Popular, though the evidence for superiority over other types is thin.
• Fan — the original, and it has the advantage of also cooling the room.

Volume and safety

• Keep it low — roughly shower-level or quieter, and well below anything you would want to hear music at. Aim for around 50 dB or less.
• Place the speaker away from the bed and away from your head.
• Do not use earbuds or in-ear headphones overnight — they are uncomfortable, and prolonged occlusion increases earwax and infection risk.
• For infants, keep any sound source well away from the cot and quiet; safe-sleep guidance matters more than masking.
• Be aware of dependence: if you cannot sleep without it, that is a cue to check whether the underlying noise problem can be solved instead.

Alternatives

• Earplugs — often more effective than masking, cheaper, and portable. Foam or mouldable wax both work.
• Solving the source — a draught excluder, a heavier curtain, moving the bed away from a shared wall.
• Routine — a consistent background sound can become part of the wind-down cue, which is a legitimate additional benefit.