A site that only manufactures backgrounds
Most image tools take something you already have and change it. This one starts from nothing and produces a rectangle of pixels at a size you name. That difference decides everything else about it.
Why manufacturing rather than editing
The request behind almost every visit here is small and specific: something needs a background, and it needs to be a particular number of pixels. Not a photograph with the background changed — a background, on its own, as a file. Stock libraries answer that with a search and a licence. Image editors answer it with six steps and a blank document. Neither is a good answer to a thirty-second problem.
So this site does one operation in depth. A ground colour, a stack of layers, a pair of dimensions, and a file. The depth goes into the parts that are usually skipped: the interpolation space a ramp runs through, the dither pass that hides eight-bit banding, the arithmetic that turns millimetres into pixels, and a weight estimate that is measured rather than guessed.
What it deliberately does not have
There is no file input on this site. Not a disabled one, not one behind a feature flag — there is no code here that decodes an image, inspects one or looks at one. That absence is a design decision rather than an omission, and it is worth being concrete about what it rules out: no colour can be lifted from a picture you have, nothing can be placed behind a person, and no photograph can be altered here in any way at all.
It also has no account, no saved projects and no server-side anything. A design you want to keep is kept by keeping its link: the entire stack is written into the address of the page as you work.
How it is built
The renderer is a few hundred lines of arithmetic over typed arrays. Every colour is held as a lightness, a chroma and a hue angle, and converted to sRGB only when a pixel is finally written, which is what makes interpolating a ramp perceptually rather than numerically the default rather than an extra. Gradients are computed from a thousand-step lookup table; noise and dither are hash functions of the pixel coordinate, which is why a design is reproducible from a number and why a large export can be drawn in bands with no seam.
The preview and the export run the same routine at different sizes. A full-size draw happens in a worker thread so the page stays responsive, and above thirty megapixels it is drawn in horizontal slices because a browser will not allocate a canvas that large in one piece. The site itself is a static export with no back end of any kind.
Who keeps it
It is part of a small group of single-purpose image sites, each of which does one operation. The footer credits PictureEditor.com as the group this one belongs to, in plain text rather than as a link. It is maintained by the same people and free to use, with no account to make and nothing to buy. Advertising on the reading pages is what is meant to pay for it, and none of it has started: Google has not approved the domain, so no advertisement is shown here at the moment.
Nothing here is sent anywhere. The file is drawn by your browser and written to your disk.