What This Fan Sound Is (and How It's Made)
This isn't a field recording. No microphone was ever pointed at a real fan for this page. It's synthesized: filtered noise shaped into a continuous rush of air, layered with a low rumble standing in for a motor, plus a faint, regular pulse where blades would pass a housing. Every sample is computed live in your browser with the Web Audio API.
That's also why there's no loop. A real recording eventually has to repeat, and most ears catch that within a few minutes. This keeps generating fresh output for as long as the tab stays open, an hour or all night, because there's no audio file behind it to run out.
What This Fan Sound Sounds Like
Think of a box fan set on its lowest speed, angled across a bedroom on a summer night: a broad, steady hiss of moving air with real weight underneath it, not a thin whistle.
The motor rumble sits low and constant, closer to a window AC unit humming in the next room than to anything sharp. Listen for the faint, regular pulse riding on top, like the soft whump of blades passing a housing — subtle, more texture than a distinct sound.
Benefits of Fan Noise for Sleep
Fans work as a sleep sound for the same reason white noise machines do: steady, broadband sound raises the floor of what your ears register, so a slamming door or traffic outside stops being the loudest thing in the room.
A fan's mix of airflow and low rumble also sits in a comfortable range, not as bright as a hair-dryer hiss, not as heavy as pure brown noise, which is likely why so many people reach for a real fan before they've ever heard of noise colors.
- Sleep: masks sudden household noise for easier, steadier sleep.
- Babies and nurseries: a steady backdrop many parents already use at bedtime.
- Focus: covers chatter and background noise during work or study.
- Light sleepers: smooths over a partner's movement or noise from another room.
- Familiarity: recreates a cue your brain may already associate with rest.
How This Player Shapes the Sound
Tone works like a lowpass filter: warm for a duller, more muffled fan, bright for more presence in the airflow hiss. Waves adds a slow swell to the volume, like a fan oscillating on a stand. Sleep Timer fades everything out over a span you choose.
A 55 Hz high-pass filter quietly removes sub-bass your speaker can't reproduce cleanly, so the rumble stays a rumble instead of a buzz. A limiter keeps the output from clipping even at higher volumes. And a generated fan skips what a real one costs you: no cold room, no bump on the electric bill, no dust.
How to Use the Fan Sound Player
Press play, set the volume to the lowest level that still covers what's bothering you, and adjust Tone until the rumble feels right. Turn on Waves if you like a fan that oscillates, and set a Sleep Timer for unattended nights. It works in any modern browser, no account or app needed — a dedicated mobile app is on the way.
This is a comfort and masking tool, not a medical treatment. Keep the volume moderate, roughly 50 decibels or lower. Near a baby, place the speaker more than 2 meters (about 7 feet) from the crib and use the timer rather than letting it run unattended. Ear pain, or new, worsening, one-sided ringing in your ears, is a reason to see a doctor or audiologist, not to turn the volume up.