Research guide

Do sound machines help sleep?

They may make sudden household or street noise feel less noticeable for some people. But they are not a proven solution for every sleep problem, and the research is more mixed than the marketing suggests.

Prepared by Bedtime Cues Editorial Team · Evidence reviewed 19 September 2026 · General education, not medical review

What the evidence says

Masking sound can help some people, but the overall evidence is uncertain.

A systematic review of 38 studies on continuous white noise and similar broadband noise found highly varied study methods and outcomes. Using GRADE criteria, it judged the evidence for continuous noise improving sleep to be very low.[1] A later review of auditory stimulation found some positive findings across white noise, pink noise and multi-audio interventions, but concluded there was still no strong evidence for routine use.[2]

The realistic use case

A steady sound may be worth trying when the main problem is unpredictable sound: traffic bursts, a neighbour’s door, an irregular partner schedule or an appliance that switches on and off.

What it cannot tell you

A sound machine does not diagnose insomnia, treat a medical sleep disorder or make a consistently loud bedroom healthy. It is an environment tool, not healthcare.

How to test one sensibly

Run a small experiment before committing to a product.

Identify the noiseNotice whether the issue is sudden changes, a constant hum, voices, traffic or another source. A steady sound will not solve every type of interruption.

Start quietlyUse the lowest comfortable volume, place the device away from your head and stop if it feels intrusive or causes discomfort.

Compare three nightsTry the same setting for a few similar nights. Keep notes about comfort and awakenings rather than relying on one unusually good or bad night.

Alternatives worth trying

Start with the source when you can.

Close a window gap, move the bed, add a door draft stopper, speak to a neighbour when appropriate, or use earplugs only if they are comfortable and you can still hear essential alarms. A fan or existing audio source may be enough for a low-cost test before purchasing a dedicated device.

Read: How loud should a sound machine be? →

Frequently asked questions

Sound machine FAQs

Can a sound machine make sleep worse?

It can if the sound is too loud, irritating, poorly placed or simply does not suit you. The research includes both improved and disrupted sleep outcomes, which is why trial and comfort matter.

Is a fan as good as a sound machine?

For someone who likes the sound and does not mind the airflow, a fan can be a practical masking-sound trial. Choose the tool that solves your specific room problem.

References

Research cited in this article

Riedy SM, Smith MG, Rocha S, Basner M. Noise as a sleep aid: A systematic review. Sleep Medicine Reviews. 2021;55:101385. doi: 10.1016/j.smrv.2020.101385. PMID: 33007706.
Capezuti E, Pain K, Alamag E, Chen XQ, Philibert V, Krieger AC. Systematic review: auditory stimulation and sleep. Journal of Clinical Sleep Medicine. 2022;18(6):1697–1709. doi: 10.5664/jcsm.9860. PMID: 34964434.