Random Bitmap Generator
Generate random pixel images and download them as PNG or BMP.
Random Bitmap Generator
Create random pixel images right in your browser. Set the width and height in pixels, choose a color mode and a zoom factor, and download the result as PNG or BMP. Use it for noise textures, placeholder art, avatar-style identicons, test images and teaching material about raster graphics.
Color modes
| Mode | What you get |
|---|---|
| Black & white | each pixel is black with the chosen probability (density), otherwise white |
| Grayscale | each pixel gets a random brightness from 0 to 255 – classic TV static |
| Full color | random red, green and blue values for every pixel |
| Custom palette | pixels picked from your comma-separated hex colors, e.g. #d10505, #ffffff |
Presets
- Identicon – 7 × 7 pixels, two colors, mirrored and zoomed 40× for a profile-picture look.
- TV noise – wide grayscale static for backgrounds and glitch effects.
- Pixel art – 16 × 16 mirrored full-color sprites; regenerate until you find a creature you like.
Uses
- Design – grain overlays, dithering patterns, retro textures and random avatars.
- Testing – image upload, compression and thumbnail pipelines with incompressible content; random noise is a worst case for PNG and JPEG.
- Education – show how width, height and color depth determine file size, or compare PNG and BMP sizes for the same picture.
- Games – procedural maps, starfields or fog-of-war masks from black-and-white noise with a low density.
About the BMP export
The BMP file is a standard 24-bit Windows bitmap: a 54-byte header followed by rows stored bottom-up, each padded to a multiple of 4 bytes. It opens in every image editor and is handy when a tool requires uncompressed input.
Everything happens locally on a canvas element; no image is uploaded. To edit an existing image, see the Image Tools.
Frequently Asked Questions
What is a random bitmap?
A raster image whose pixels are chosen at random – black and white noise, grayscale static, full-color noise or pixels drawn from your own palette. With Mirror enabled the left half is reflected to the right, which produces symmetric shapes similar to GitHub identicons.
Which file formats can I download?
PNG (lossless and small) and BMP (uncompressed 24-bit Windows bitmap). Both are exported at the zoom shown in the preview, so every random pixel becomes a crisp square block.
How large can the image be?
Up to 1024 × 1024 random pixels. The zoom is reduced automatically so the exported image never exceeds 4096 pixels on a side.
Is the noise suitable for cryptography?
Pixels are drawn from the browser's cryptographically secure generator, but an image is not a key format. Use the Random Byte Generator if you need raw secure random bytes.