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Reference Formats

BMP

An uncompressed (or lightly RLE-compressed) Windows-native raster format with no meaningful metadata support, retained mainly for legacy compatibility.

Extension

.bmp

Full name

Windows Bitmap (Device-Independent Bitmap)

Introduced

1987 (Windows 2.0 original header); formalized with BITMAPINFOHEADER in Windows 3.0, 1990

Vendor

Microsoft Corporation (co-developed with IBM for OS/2)

What is inside the container

BMP is stored uncompressed by default, with optional 4-bit or 8-bit RLE compression available only for palette (indexed) images; 16-, 24-, and 32-bit true-color images are always uncompressed or bitfield-encoded. It supports 1, 4, 8, 16, 24, and 32 bits per pixel. There is no EXIF, IPTC, or XMP support at all; ICC profile embedding exists only in the rarely-used BITMAPV5HEADER variant, and ExifTool lists BMP as read-only for metadata, confirming it cannot meaningfully carry DAM metadata.

How to open it

macOS Preview (native)
Windows Photos app and Paint (native, built into GDI since Windows 3.0)
Web browsers All major browsers render BMP natively via
Cross-platform GIMP, Photoshop, IrfanView, ImageMagick all read/write BMP

For archives

Do not use as a DAM master or preservation format. Uncompressed BMP wastes storage with no compensating benefit — no meaningful metadata capacity and essentially no color-management adoption in practice. Convert incoming BMPs to TIFF (lossless, with real metadata support) on ingest.

BMP solved a narrow, early problem: Microsoft and IBM needed a simple, guaranteed-decodable raster format baked directly into the Windows GDI and OS/2 Presentation Manager, so any application could read and write bitmaps without licensing a codec. The original 12-byte header shipped with Windows 2.0 in 1987 and was reused in OS/2 1.1 the following year; the larger BITMAPINFOHEADER most BMP files use today — with 16/32-bit color and optional RLE compression — arrived with Windows 3.0 in 1990.

BMP predates every modern metadata standard — EXIF didn’t exist until 1994, XMP until 2001 — which is exactly why it never gained real support for either. In a DAM, BMP typically appears only as a legacy ingest artifact: old scans, screen captures, or output from older scientific or industrial imaging equipment. Thumbnailing is trivial since there’s no compression to decode, but there is effectively nothing to extract from the file itself for search indexing.

The practical DAM policy is straightforward: normalize any incoming BMP to TIFF or PNG immediately on ingest. This both shrinks the file (BMP’s default uncompressed storage is wasteful) and gives the asset a real chance at carrying metadata going forward, since BMP’s rare ICC-capable header variant (BITMAPV5HEADER) is almost never actually used by the software producing BMP files in the wild.

Frequently asked

Should a DAM use BMP as a master or preservation format?

No. Uncompressed BMP wastes storage with no compensating benefit — it has no meaningful metadata capacity and essentially no color-management adoption in practice. Convert incoming BMPs to TIFF on ingest.

Does BMP support EXIF, IPTC, or XMP metadata?

No. There is no EXIF, IPTC, or XMP support at all in BMP; ICC profile embedding exists only in the rarely-used BITMAPV5HEADER variant, and ExifTool lists BMP as read-only, confirming it cannot meaningfully carry DAM metadata.

Why does BMP lack modern metadata support?

BMP predates every modern metadata standard — EXIF didn't exist until 1994 and XMP until 2001 — which is exactly why the format never gained real support for either.

Is a BMP file compressed?

BMP is stored uncompressed by default. Optional 4-bit or 8-bit RLE compression is available only for palette (indexed) images; 16-, 24-, and 32-bit true-color images are always uncompressed or bitfield-encoded.

Where does BMP typically show up in a DAM today?

Almost always as a legacy ingest artifact — old scans, screen captures, or output from older scientific or industrial imaging equipment — rather than as a format anyone chooses deliberately.

What bit depths does BMP support?

1, 4, 8, 16, 24, and 32 bits per pixel.

What's the recommended DAM ingest policy for BMP files?

Normalize any incoming BMP to TIFF or PNG immediately on ingest. This shrinks the file and gives the asset a real chance at carrying metadata going forward.

Is BMP widely compatible across platforms?

Yes — native support has been built into Windows GDI since Windows 3.0, and all major browsers and cross-platform tools (GIMP, Photoshop, IrfanView, ImageMagick) read and write it without issue.

Sources