What is a TIFF file?

TIFF is a container: a wrapper that holds streams encoded by something else. It stores a grid of pixels, so enlarging it past its own resolution softens it. It is used for print, scanning and archiving.

The extension is .tif, and the full name is Tagged Image File Format. Both matter less than what the file can hold, which is what the rest of this page is about.

Adobe published it in 1986. The specification is TIFF 6.0.

A format that has been readable for that long is a format worth trusting with something you want back in ten years.

It is written down and implementable, though the vendor decides what the next version looks like. In practice that is enough for the file to keep opening; it is not enough to be sure of it.

TIFF stores its content exactly. Saving it again changes nothing, so it can be opened, edited and re-saved as often as you like without accumulating damage — which is what makes it a working format rather than a delivery one.

TIFF carries an alpha channel, so a logo keeps its soft edges over whatever sits behind it instead of arriving in a white box.

Up to 32 bits per channel. It can work in RGB, CMYK, the model a printing press needs, greyscale and Lab.

CMYK is the one that decides whether a printer accepts the file, and it is the thing most often lost converting to a screen format.

TIFF is not limited to one page, which matters when converting to something that is: one conversion produces one file holding a single page — the first one, unless the page is something the converter lets you pick.

TIFF stores the parts of an image separately rather than flattened together, which is what makes it a working file. Almost every format it converts into flattens them, and the flattening is not reversible — keep the layered original.

Also known as TIF. Worth knowing when searching for a program that handles it: the name on the specification and the name on the menu are not always the same one.

Adobe Photoshop, Affinity Photo and ImageMagick read it, and so do most programs of the same kind.

If a file will not open, the format is rarely the problem — it is more often that the program predates it. Converting to something older is the reliable way past that, and it is what the rest of this site is for.

Only some browsers read it.

Where support is uneven, serving a second format alongside it is the usual answer — the browser takes the one it understands and nobody is left out.

TIFF can hold EXIF, XMP, IPTC, ICC profiles and GPS coordinates.

The GPS coordinates are the field worth thinking about before sending a file anywhere: they say where the photograph was taken, and almost nothing warns you that they are still in there.

TIFF is meant to be opened and changed. Keep the file in this format for as long as the work is going on, and export from it whenever a finished copy is needed.

The recurring complaints: the files are large for what they contain and support outside its home ground is uneven.

None of these is a reason to avoid the format. They are the things worth knowing before you are surprised by one, which is a different claim and a more useful one.

TIFF does not define one arrangement of bytes. It defines a container built from tags — numbered fields describing width, height, bit depth, colour model, compression method, layout — and almost all of it is optional. Two files can both be valid TIFFs and share almost nothing.

That is the whole reason TIFF has a reputation for being awkward. A program does not implement TIFF; it implements the subset of tag combinations it expects, and everything else is a coin toss. When one TIFF opens and another from the same scanner does not, that is why — and it is a property of the design rather than a bug in either.

A great many TIFFs carry no compression at all, storing every pixel as raw bytes. An A4 page scanned at 300 dpi in colour is about 25 megabytes; the same page at 600 dpi is around 100. Nothing has gone wrong — the file simply contains exactly what the scanner measured.

Compression is available and comes in incompatible flavours: LZW and Deflate are lossless and widely read, PackBits is a simple run-length scheme, Group 3 and Group 4 are the fax encodings for black-and-white documents, and JPEG-in-TIFF is lossy. Which one a file uses decides whether a given program can open it, and there is no way to tell from the name.

ARW, NEF, ORF, RAF, CR2 and DNG are all built on TIFF’s tag structure. A camera manufacturer designing a raw format did not invent a container; it took TIFF, added private tags for sensor data and lens corrections, and changed the extension.

This explains a great deal about how raw files behave. It is why software that reads one manufacturer’s raw has a running start on another’s, why raw files carry EXIF the way TIFFs do, and why a raw file will sometimes partially open in an image program that has never heard of the camera. Canon’s CR3 is the notable break — it abandoned TIFF for the ISO base media format, and support had to be rebuilt from nothing.

TIFF supports multiple images in one file, which is how document scanners store a multi-page scan. Each page is a complete image with its own tags, chained together.

This is the single most common surprise when converting one. JPG and PNG hold exactly one picture, so converting a ten-page TIFF produces the first page and discards the rest. PDF is the only common target that has pages at all, and this converter does not use them either: it reads the first image in the file and stops, so a ten-page TIFF becomes a one-page PDF. A document that has to keep its pages has to come from the scanner or the records system that wrote the TIFF.

Document and records management in law, insurance and healthcare. Court and government submission systems specified decades ago. Print production, where CMYK TIFFs remain a standard delivery format. Archival standards, several of which name it explicitly. Scientific and medical imaging. And scanning software that has written TIFF since the 1980s and sees no reason to stop.

The thread is institutions that chose a format once and built processes around it. Nobody picks TIFF for convenience in 2026 — it is picked for you, and that is the situation nearly everyone converting one is in.

Archival specifications frequently demand bitonal TIFF: one bit per pixel, pure black or pure white, usually with Group 4 fax compression. For printed text it is remarkably efficient — a scanned page can be under 100 kilobytes.

Producing it means choosing a threshold, and choosing badly destroys thin strokes, faint stamps, pencil annotations and anything grey. Software built for scanning does this well, with adaptive thresholds that vary across the page. A general converter guessing at one value does not, which is why bitonal conversion belongs in the scanning step rather than afterwards.

TIFF can carry an alpha channel, and Photoshop can store layers inside one using private tags. A layered TIFF opens in Photoshop with its layers intact and opens everywhere else as a flattened composite.

That is not damage and nothing is lost from the file — the other program simply does not read the private tags. It does mean a layered TIFF is much larger than it appears to justify, and that sending one to someone without Photoshop delivers a flat image regardless of what you saved.

TIFF handles 16 bits per channel where JPG and PNG in general use handle 8 — 65,536 levels against 256. Scanners, cameras and print workflows write it, and it is one of the reasons TIFF persists in serious imaging.

It matters in one place: editing. The extra headroom is what stops a strong curve or exposure adjustment from banding a gradient. For viewing, sending or publishing it makes no difference at all, which is why converting to an 8-bit format is usually harmless and why keeping the TIFF is still right if the image will be worked on again.

PNG when every pixel must survive — same lossless content, a fraction of the size, and every program from this century opens it. JPG when the file must be small enough to send and the content is photographic or a document that will be read rather than analysed. PDF when the result has to be filed, printed or attached as a document rather than as an image — remembering that only the first page of the TIFF arrives in it.

Keep the TIFF if it is an original scan of something that cannot be rescanned, or if a system on the receiving end has asked for it by name. Given what people scan — contracts, medical records, legal filings, identity documents — converting in the browser rather than uploading matters here more than almost anywhere else on this site.