TIFF-FX

TIFF for Facsimile eXtended

image/tiff-fx Released 1998 · by IETF (Internet Engineering Task Force)

The image/tiff-fx MIME type represents TIFF for Facsimile eXtended (TIFF-FX), a specialized profile of the Tagged Image File Format designed specifically for transmitting multi-page facsimile (fax) documents over the Internet. It defines specific profiles for black-and-white, grayscale, and color faxing, standardizing how fax data is encapsulated for email (Internet Fax) and IP network transmission.

Telecommunications & Fax Production Ready

Technical Specifications

MIME Type

image/tiff-fx

Extensions

.tiff.tif

Container

TIFF 6.0 Tag Directory Structure

Compression

MH / MR / MMR (CCITT Group 3 & 4) & JBIG & JPEG

Algorithms

CCITT Group 3/4JBIGJPEG

Color Depth

1-bit (Monochrome B&W), 8-bit (Grayscale/Color Indexed), 24-bit (RGB Color)

Metadata

XMP ICC

Capabilities

Transparency

Animation

Progressive Loading

Alpha Channel

HDR Support

Official Specification

Aliases: image/tiff

Magic Bytes & HTTP Headers

File Signature (Magic Bytes)

49 49 2A 00 (Little-Endian) / 4D 4D 00 2A (Big-Endian)

ASCII: II*\x00 / MM\x00*

HTTP Headers

Content-Type: image/tiff-fx

HTML Accept Attribute

accept="image/tiff-fx, .tiff, .tif"

Browser Support Matrix

Browser	Status	Min Version
Chrome	Not Supported	—
Firefox	Not Supported	—
Safari	Not Supported	—
Edge	Not Supported	—
Internet Explorer	Not Supported	Legacy

Advantages & Limitations

Advantages

Provides a universal, standardized format for transmitting multi-page documents over IP networks and email (Internet Fax)
Supports highly efficient telecom-centric compression algorithms (MMR, JBIG) that produce very small files for text documents
Maintains backwards compatibility with standard TIFF parsers

Limitations

Not supported natively by web browsers
Requires complex parsing of TIFF IFD tags to differentiate a true TIFF-FX file from a standard TIFF file
Usage is slowly declining as traditional faxing is replaced by secure PDF transmission and e-signature platforms

Developer Code Snippets

import magic
# Libmagic will typically identify this simply as a TIFF file, not explicitly TIFF-FX
print(magic.from_file('fax.tif', mime=True)) # Outputs 'image/tiff'

const FileType = require('file-type');
const type = await FileType.fromFile('fax.tif');
console.log(type.mime); // Outputs 'image/tiff'. Identifying TIFF-FX requires parsing the internal IFD tags.

import "net/http"
// http.DetectContentType will return 'image/tiff' based on the II* or MM* magic bytes.

$mime = mime_content_type('fax.tif');
echo $mime; // Standard server setups resolve this to 'image/tiff'

File Detection Steps

How to programmatically detect a image/tiff-fx file by reading its raw bytes:

1 Check the first two bytes for TIFF endianness (49 49 or 4D 4D)
2 Verify the 42 identifier (2A 00 or 00 2A)
3 Parse the IFD (Image File Directory) tags to verify fax-specific parameters such as GlobalParametersIFD (Tag 400) or specific PhotometricInterpretation and Compression tags associated with Profiles S, F, J, C, L, or M

Software Support

H

HylaFAX

W

Windows Fax and Scan

L

LibTIFF

ImageMagick

Conversion Tools

Share & Embed

Markdown Badge

[![TIFF-FX Format](https://freewebptojpg.com/mime/image/tiff-fx/badge.svg)](https://freewebptojpg.com/mime/image/tiff-fx)

Interactive iframe Widget

<iframe src="https://freewebptojpg.com/mime/image/tiff-fx/embed" width="100%" height="280" style="border:1px solid #cbd5e1;border-radius:8px;" title="TIFF-FX Specs"></iframe>

JSON API

All data on this page is available as a free, open JSON API. Use it in your project, documentation, or tooling.

GET https://freewebptojpg.com/mime/image/tiff-fx.json Open JSON

Free to use

No auth required

CORS enabled

Use from any domain

Cached 24h

Cache-Control headers set

Frequently Asked Questions

What is the difference between image/tiff and image/tiff-fx?

Structurally, a TIFF-FX file is a standard TIFF file. However, image/tiff-fx guarantees that the file adheres to strict Internet Fax profiles (Profiles S, F, J, C, L, or M) defined by the IETF. This ensures compatibility with VoIP fax gateways, fax machines, and enterprise fax servers.

What compression algorithms does TIFF-FX use?

Depending on the fax profile, TIFF-FX supports Modified Huffman (MH), Modified Read (MR), Modified Modified Read (MMR) for standard B&W faxes, JBIG for high-compression B&W or color, and JPEG for standard color faxes.

Can I open a TIFF-FX file in a standard image viewer?

Yes, in most cases. Because TIFF-FX is built on the standard TIFF 6.0 structure, robust image viewers and operating system previewers can usually open and display the pages, provided they support the specific compression algorithm (like MMR or CCITT Group 4) used inside the file.