GIF to BMP Converter

Encoding: the GIF uses lossless LZW over a palette of at most 256 colours; BMP uses usually none; RLE for some 4 and 8-bit files, and the download is an uncompressed 24-bit BMP, or 32-bit with alpha when the image has transparency.

Bit depth: 8 bits per pixel, as indexes into a palette in the GIF; BMP allows 1, 4, 8, 16, 24 or 32 bits per pixel, and the BMP written here has 24 or 32 bits per pixel.

Colour: an indexed palette of up to 256 colours per frame in the GIF; BMP supports RGB or an indexed palette, written here as 8-bit sRGB.

Transparency: the GIF stores it as one palette entry marked transparent, so each pixel is either fully shown or fully hidden; the BMP keeps it as an optional fourth byte in 32-bit files, which many programs ignore.

Animation: image blocks with their own delay and disposal method, looped by the NETSCAPE2.0 extension; the BMP holds one image, so only the first frame is converted.

Metadata: the GIF can carry comment and application extension blocks, but no EXIF; BMP can carry nothing beyond the header's resolution fields (and a colour profile in rare V5 headers), but nothing is copied across.

GIF is the classic animated image format. It is limited to 256 colours per frame and 1-bit transparency, so photos look grainy and files are large, but it plays everywhere.

A GIF starts with 'GIF89a' (or the older 87a), a logical screen descriptor and an optional global colour table, then image blocks, each preceded by a graphic control extension that sets its delay and transparent colour.

GIF files usually come from reaction clips, memes, old websites and screen recordings.

BMP stores raw, uncompressed pixels. Files are huge but trivially simple, which is why some legacy Windows software, embedded displays and printers still ask for it.

A BMP is a 14-byte file header ('BM' and the offset to the pixels), a DIB header (40 bytes, or 108 and 124 bytes in the V4 and V5 versions that add colour masks and alpha), an optional palette, then pixel rows padded to 4 bytes and normally stored bottom-up.

BMP is the better choice for legacy software and embedded systems that require it, while GIF suits short animations and reactions that must play everywhere.

BMP strengths: No compression artifacts; Read by very old and very simple software. Drawbacks to weigh: Enormous files; Poor support for transparency; No metadata.