Tagged Image File Format

TIFF (Tagged Image File Format, extensions .tif and .tiff) is the workhorse of scanning, archiving and print. Archives and libraries keep master scans in it, print shops and photographers exchange 16-bit and CMYK images in it, fax and document systems store multi-page black-and-white documents in it, and GIS maps travel as GeoTIFF. If you received a TIFF, it most likely came from a scanner, a digitisation service, a photographer or a print shop.

History

Aldus, the maker of PageMaker, published TIFF in 1986 together with Microsoft, to give the first desktop scanners a common format. Revision 5.0 (1988) added palette colour and LZW compression, revision 6.0 (1992) JPEG compression, CMYK and tiles. In 1994 Adobe acquired Aldus and has controlled the specification ever since; 6.0 is still the current revision, extended by technical notes such as Deflate (ZIP) compression. Many standards are built on TIFF: TIFF/EP (ISO 12234-2) for cameras, which is also the basis of DNG and of raw formats such as CR2 and NEF; TIFF/IT (ISO 12639) for prepress; and GeoTIFF for maps with coordinates.

How TIFF works

• Tags. After the header (II or MM for byte order) come directories of tags: width, height, compression, colour space, resolution, and dozens more. Each directory describes one image, so a file can hold any number of pages.
• Compression by choice: none, PackBits, LZW and Deflate (all lossless), JPEG (lossy) and CCITT Group 3 and 4 for black-and-white fax and document scans, where a page takes only tens of kilobytes.
• Colour: 1 to 32 bits per channel including floating point, greyscale, RGB, CMYK, CIE Lab, alpha channels, ICC profiles.
• Limits: classic TIFF uses 32-bit offsets, so a file cannot exceed 4 GB. Larger images use the BigTIFF variant with 64-bit offsets, which older programs do not read.
• Layers? Photoshop can save layers into a TIFF in its own private tag. Other programs show only the flattened image.

This flexibility is TIFF's weakness too. Two files with the same extension can differ completely inside, and a program that understands one may refuse the other.

Opening and editing TIFF

Windows opens TIFF in Photos, macOS in Preview, which shows the pages of a multi-page file in the sidebar. On Linux, image viewers and GIMP handle it; GIMP asks whether to open pages as layers or separate images. For professional work there is Photoshop or Affinity Photo, for quick viewing IrfanView or XnView MP. On phones support varies: iPhone shows TIFF in Files, many Android galleries do not show it at all. The open-source library LibTIFF and its tools (tiffinfo, tiffsplit) reveal what a problematic file really contains.

Common TIFF problems

TIFF won't open

The cause is usually an unusual variant: old-style JPEG compression from the 1990s, 16-bit or 32-bit floating-point data, CMYK, BigTIFF or a fax file with unusual parameters. Try a different program; if one opens it, export to a standard format. Our converter reads most TIFF variants.

Only the first page of a TIFF is shown

Many viewers and upload forms ignore further pages. Convert the multi-page TIFF to PDF, where every page remains.

TIFF is too large to e-mail

An A4 page scanned in colour at 600 dpi is about 100 MB uncompressed. For sending, PDF or JPG is enough; keep the TIFF as the archive master.

Converting TIFF

Most often TIFF goes to PDF (documents, fax, scans) and to JPG for sharing and the web, see TIFF to JPG. How our converter handles pages: TIFF to PDF keeps all pages in one document; TIFF to JPG, PNG or BMP takes only the first page. In the other direction, PDF to TIFF renders every page at 150 dpi into one multi-page TIFF. Transparency survives in PNG and TIFF, in JPG it becomes white; 16-bit data become 8-bit in JPG. Photoshop layers are not converted, only the composite image. Images over 30,000 pixels on a side cannot be processed.

TIFF at a glance

More: Library of Congress on TIFF 6.0, on TIFF/EP, and the LibTIFF project.