TIFF to BMP Converter

Encoding: the TIFF uses none, LZW, PackBits, Deflate or JPEG, chosen per file; 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: 1 to 16 bits per channel, or 32-bit floating point in the TIFF; BMP allows 1, 4, 8, 16, 24 or 32 bits per pixel, and the BMP written here has 24 or 32 bits per pixel. 16-bit and floating-point TIFFs are reduced to 8 bits per channel.

Colour: RGB, CMYK, Lab, greyscale or palette, often with an ICC profile in the TIFF; BMP supports RGB or an indexed palette, written here as 8-bit sRGB.

Transparency: the TIFF stores it as an extra sample declared in the ExtraSamples tag; the BMP keeps it as an optional fourth byte in 32-bit files, which many programs ignore.

Other images: the TIFF can hold several pages, each in its own image file directory; only the main image is converted.

Metadata: the TIFF can carry EXIF, XMP, IPTC and ICC, all stored as tags; BMP can carry nothing beyond the header's resolution fields (and a colour profile in rare V5 headers), but nothing is copied across.

TIFF is the professional archive and print format. It can hold multiple pages, high bit depths and lossless data, and is common in scanning, publishing and GIS.

A TIFF begins with 'II' or 'MM' for the byte order and the number 42, then an offset to the first image file directory (IFD): a table of tags giving the size, compression, colour model and the location of the strips or tiles of pixels. Each further page is another IFD.

TIFF files usually come from scanners, print and publishing workflows, photo archives and tethered camera capture.

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 TIFF suits printing, scanning and archival masters.

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