A BMP file is an uncompressed raster image comprised of a rectangular grid of pixels. It contains a file header (bitmap identifier, file size, width, height, color options, and bitmap data starting point) and bitmap pixels, each with a different color.

BMP file open in Microsoft Windows Photos 10 BMP files may contain different levels of color depths per pixel, depending on the number of bits per pixel specified in the file header. They may also be stored using a grayscale color scheme. You can open BMP files using programs bundled with Windows and macOS. In Windows, you can open BMP files in Microsoft Windows Photos. In macOS, you can view BMP files with Apple Preview or Apple Photos. A large number of image and graphics programs also can be used to open BMP files, including Adobe Photoshop, Adobe Illustrator, CorelDRAW, and ACD Systems Canvas. Many of these programs may also be used to create BMP files.