How to use the fan noise generator
- Turn your device volume down, then press Play. The sound fades in at 25% volume.
- Pick a fan type: Box fan, Desk fan, Ceiling fan or Air conditioner.
- Set the Speed. Faster sounds brighter and louder, just like a real fan.
- Add Hum to taste. A little for a fan, more for an air conditioner.
- Oscillate (desk fan only) makes the sound sweep slowly from side to side.
- Set the sleep timer and fade-out, then lock your phone or press ◐ Dim screen.
With the tool focused, Space or K plays and pauses, 1 to 4 pick the fan type, [ and ] change the speed, ↑ and ↓ change the volume, and D dims the screen.
Box fan, desk fan, ceiling fan or AC: what’s different
Box fan is the default, because the box fan sound is what most people grew up sleeping with: a steady rush of air with a low thrum from the big blades. At low speed it’s soft and dark; at high speed it fills the room.
Desk fan is brighter and lighter, with smaller, faster blades. With Oscillate on, it sweeps across you every 16 seconds and sounds a little brighter each time it faces you, like a real oscillating fan.
Ceiling fan is the softest: a deep, slow whoosh that pulses as the blades pass overhead. Faster speeds make the pulse quicker.
Air conditioner is brighter, steadier airflow with a stronger hum, like the compressor and fan of a window unit. It drifts very slowly in level, as real units do.
How the fan sound is made
The fan noise is generated live from three ingredients. The first is airflow: filtered noise, which gets brighter and louder as the speed goes up. The second is the blades: a box or desk fan adds a low thrum around the blade-pass rate, and a ceiling fan pulses its whoosh. The third is motor hum: a tone at twice the power-line frequency, 120 Hz with 60 Hz power or 100 Hz with 50 Hz power, with weaker overtones above it.
Everything is synthesized in your browser and tuned by ear. It sounds like a fan, but it isn’t a recording of any specific model, so it never loops, never ends and has no seam. Phone speakers barely play the hum, because 100 to 120 Hz is close to the lowest notes they can reproduce; with headphones or a bigger speaker you’ll hear it clearly.
Fan noise vs white noise
A fan’s sound is mostly low-frequency airflow plus a few tones, so it’s deeper and warmer than white noise, which spreads its energy evenly and sounds like a hiss. In color terms, fan noise sits closer to pink noise or brown noise.
Many people call any steady background sound “white noise”, which is why the phrase “white noise fan” is so common. If you like the masking of a fan but want something smoother, try pink noise; if you want it brighter, try white noise. All of them work the same way: a steady sound makes changing noises, like traffic or voices, less noticeable.
Why is my box fan making noise?
Unplug the fan before you check anything. Common causes:
- Rattling: loose screws, a loose grille or a loose knob. Tighten them.
- Wobbling or ticking: a bent or unbalanced blade. Straighten it gently or replace the blade set.
- “Sounds like it’s hitting something”: a blade touching the grille. Check that the grille isn’t bent inward.
- Whirring that got louder over time: dust on the blades and grille. Clean them.
- Squealing or grinding: worn motor bearings. Some fans can be oiled; check the manual.
- Humming or buzzing through the floor: vibration. Set the fan on a flat, solid surface.
If the fan grinds, smells hot or burnt, or the motor gets very hot, stop using it and replace it.
Laptop fan noise is a different problem
A laptop fan speeds up when the processor is busy or the vents are blocked. Check what’s using the processor in Task Manager on Windows or Activity Monitor on a Mac, keep the vents clear of blankets and dust, and use the laptop on a hard surface.