cv.cm
All tools

White noise generator

The noise is made in this tab. Nothing is uploaded.

Stopped.

White noise
Equal energy at every frequency: a bright hiss, like a detuned radio.
Pink noise
Softer highs (−3 dB per octave): steady rain or wind.
Brown noise
Deep and rumbling (−6 dB per octave): distant surf or a waterfall.
Green noise
Centred on the mid range around 500 Hz: a calm, natural hum.

How to use this tool

Play white, pink, brown or green noise for sleep or focus, with a sleep timer. Nothing is uploaded.

  1. Open White noise generator

    Pick a Noise colour. The line under it says how each one sounds.

  2. Set the volume and timer

    Start with a low Volume. Choose a Sleep timer, or leave it Off to play until you stop it.

  3. Play

    Press Play. You can switch colour or volume while it plays; the timer fades it out at the end.

How-to guides

FAQ

What is the difference between white, pink and brown noise?

White noise has equal energy at every frequency and sounds like hiss. Pink noise drops 3 dB per octave and sounds like steady rain. Brown noise drops 6 dB per octave and sounds like a low roar or distant surf. Green noise is centred on the middle of the range, around 500 Hz.

Which noise is best for sleep?

There is no single best one. Many people find pink or brown noise softer than white noise. Try each at a low volume for a few minutes and keep the one you notice least.

How does the sleep timer work?

Pick 15 minutes to 8 hours before pressing Play. The sound fades out over the last 30 seconds and stops. The fade is scheduled in the browser's audio engine, so it ends on time even in a background tab.

Is it safe for babies?

Keep the volume low, put the speaker well away from the cot and use the sleep timer. A 2014 study in Pediatrics found that some infant sound machines can pass 85 dB at full volume; hospital nurseries are kept under about 50 dB. You can check the level with the cv.cm decibel meter.

Does it need the internet or upload anything?

The noise is generated in your browser, so once the page has loaded it plays without any download. Nothing is uploaded.