image/bmp

Windows' native bitmap, in use since the 1980s but only formally registered in 2016 by the RFC that cleaned up the Windows image types. It is usually uncompressed, so files are enormous by modern standards — send it only when a legacy Windows toolchain or embedded device demands it, never as a web format. Before registration it traveled under image/x-bmp and image/x-ms-bmp, labels you will still meet in old upload pipelines.

.dib (device-independent bitmap) is the same format under its older, more literal name.

Defined by RFC 7903 · IANA registration. Registry facts from the IANA media-types registry via mime-db.