Why does the same seed always give the same file?

It selects the starting point of the random sequence. The same seed with the same amplitude and duration always produces an identical file, while a different seed produces different samples at the same statistical character. Keep the seed if a file may need to be regenerated exactly.

Why is the output not the same loudness as another generator's?

Because amplitude is a scaling factor rather than a level. Noise has no single amplitude the way a tone does: its samples are spread across a range, and the perceived loudness depends on the distribution as much as on the peak. Use the meter tools if a precise level is required.

What makes white noise white?

Equal energy per hertz across the whole band, the audio equivalent of white light containing all visible frequencies. Every octave therefore contains twice as much total energy as the octave below it, which is why white noise sounds bright and hissy rather than balanced.

Can I make it quieter and easier to listen to?

Lower the amplitude, or use pink noise instead. Pink noise falls by three decibels per octave, giving equal energy per octave, which matches how hearing works and sounds far more natural. Brown noise falls faster still and is closer to a rumble.

Does the noise repeat if I loop the file?

It loops as a file of finite length rather than as a continuous stream, so a loop point can be audible as a small click because the last sample rarely matches the first. Longer durations push that repeat further apart, and a gentle fade at each end removes the click.

White Noise Generator

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White Noise Generator produces noise with equal energy at every frequency, the reference signal for testing and masking. A seed control makes each file reproducible, so the same settings always yield the same samples.

What is White Noise Generator?

The options are deliberately few: an amplitude percentage, a duration, and a seed. Press generate and the samples are computed immediately, with a player and a download link for the resulting WAV.

What the panel controls and reports:

An amplitude slider from one to one hundred percent, defaulting to thirty.
A duration from a tenth of a second to sixty seconds, defaulting to five.
A seed field, defaulting to 12345, which fixes the random sequence so a file can be regenerated identically later.
A readout giving the seed, the sample count and the duration in seconds alongside the amplitude.

Each sample is drawn from a uniform random source and scaled by the amplitude, which gives a flat spectrum: equal energy in every frequency band, with no tilt toward the low end or the high end. Uniform noise of this kind has a root-mean-square level of roughly the amplitude divided by the square root of three, and a peak that sits close to the amplitude for short files and rises slowly as files get longer, since more draws give more chances of a large excursion. The generator is a small linear congruential sequence seeded from the number you enter, which is what makes the output reproducible. That determinism matters more than it might seem: a repeatable noise file lets you compare two identical test runs, or extend a file later without changing its character, which is impossible with a source that reshuffles every time. One practical consequence is worth noting: because the sequence is fixed by the seed and the sample positions are fixed by the sample rate, a file generated at 44.1 kilohertz and one generated at 48 kilohertz from the same seed will not contain the same samples, only the same character. Matching files across rates therefore means regenerating at the rate the file is meant to be delivered at. The amplitude scaling is applied after each draw, so the distribution of values is unaffected by the level you choose.

What white noise is not:

It is not calibrated in decibels, so the amplitude value is a scaling factor rather than a level reference.
The randomness is a simple linear sequence, which is entirely adequate for audio but not suitable for any cryptographic use.
There is no filtering, so the flat spectrum cannot be tilted, shaped or band-limited here.
The file is mono, with no option for independent noise per channel.
Nothing is trimmed or faded at the boundaries, so a very short file may begin and end on a non-zero sample and click when looped.
The maximum duration is sixty seconds per file.

Use it for the jobs noise does best: masking a conversation in an adjacent room, checking whether a speaker or headphone reproduces the full range evenly, exercising a noise gate or denoiser during development, or giving a reverb something broadband to work on. For a sound that is easier on the ear, pink and brown noise tilt the spectrum downward, and the room tone generator builds the hum and air of an actual space out of filtered noise.

How to use White Noise Generator

Set the amplitude and the duration you need.
Leave the seed alone for a reproducible file, or change it to get a different random sequence at the same settings.
Press generate to synthesise the noise and encode the WAV.
Preview it and download, using the recorded seed if the same file has to be made again later.

When to use White Noise Generator vs related tools

White Noise Generator is the reference for broadband testing and straightforward masking, where equal energy across the band is what you want. Pink Noise Generator and Brown Noise Generator tilt the same idea toward the low end for a gentler sound, and Room Tone Generator turns filtered noise into the ambience of a specific space. To check what the noise actually contains, Spectrum Analyzer shows the spectrum directly.

Privacy & Security

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