What a pixel contains
On its own, a pixel has no fixed physical size. It is a position in a grid plus color values, usually separate amounts of red, green, and blue, that a display turns into light.
Because pixels are samples rather than objects, the same grid can be shown on a small phone or a large monitor. On-screen size depends on the display, while the data stays unchanged.
From pixels to a visible image
Images store pixels in rows, and the count along each edge is the resolution. A 1,200 by 800 picture holds 960,000 pixels, each one contributing a single dot of tone and color.
Viewed from normal distance the eye blends neighboring pixels, so gradients look continuous. Move close enough, or zoom far enough, and the individual squares become visible as blocky edges.
- Width and height in pixels give the image dimensions
- Total pixel count drives storage and memory use
- More pixels preserve finer detail when magnified
- Each pixel stores color through its channel values
Pixels, files, and practical limits
Every extra pixel adds data, so pixel count is the first lever when a file is too large. Trimming dimensions reduces size faster than compression alone, with visible loss only if you cut more than the display needs.
Filekind accepts images up to 16,000 pixels on a side and 48 megapixels in total, which covers typical phone and camera output while keeping browser processing responsive.