FAX to HDR Converter

Digitize FAX files to HDR — free online converter

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Secure Processing

Source FAX files are deleted instantly after conversion. HDR output files are auto-removed within 24 hours.

Multiple Files

Process several FAX files in a single session. Each produces a separate HDR file for individual download.

Fax Preservation

Preserve fax content by converting FAX to widely supported HDR — future-proof your document archive.

How to convert FAX to HDR

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

Choose hdr or any other format you need as a result (more than 200 formats supported)

Let the file convert and you can download your hdr file right afterwards

About formats

FAX is a generic image file extension associated with facsimile transmission formats standardized by the ITU-T (formerly CCITT), with the underlying Group 3 compression standard ratified in 1980. FAX files typically contain monochrome (1-bit, black and white) image data compressed using the Modified Huffman (MH) encoding defined in ITU-T Recommendation T.4, which assigns variable-length codes to run lengths of consecutive white or black pixels along each scanline. The standard resolution for Group 3 fax is 204x98 dpi (normal mode) or 204x196 dpi (fine mode), reflecting the capabilities of thermal and laser fax machines of the era. FAX files encountered digitally are often raw Group 3 encoded bitstreams or TIFF wrappers with CCITT Group 3 compression (TIFF compression tag 3). The Group 3 encoding scheme is highly efficient for typical business documents — pages with mostly white space and black text — achieving compression ratios of 10:1 to 20:1 compared to uncompressed bitmaps. One advantage is universal fax system compatibility: Group 3 encoding is the mandatory baseline for all fax machines worldwide, meaning FAX files contain data in exactly the format transmitted over telephone lines, preserving the original fax data without transcoding losses. The format's role in business communications history provides another dimension — billions of fax transmissions using this encoding moved legal documents, medical records, and business correspondence for decades, and archived FAX files represent an important documentary record. FAX images can be viewed and converted using LibreOffice, ImageMagick, GIMP, and standard document management systems.

Developer: ITU-T

Initial release: 1980

HDR (also known as RGBE or Radiance HDR) is a high-dynamic-range image format created by Greg Ward Larson as part of the Radiance lighting simulation system, developed at Lawrence Berkeley National Laboratory starting in 1985 with the HDR format emerging around 1989. The format stores floating-point RGB pixel values using a compact 32-bit-per-pixel encoding called RGBE (Red, Green, Blue, Exponent): three 8-bit mantissa bytes share a single 8-bit exponent, representing luminance values across a range of roughly 76 orders of magnitude while keeping file sizes comparable to standard 24-bit images. HDR files begin with a text header containing rendering and exposure metadata, followed by the RGBE pixel data compressed with a scanline-oriented run-length encoding scheme. The format captures the full luminance range of real-world scenes — from deep shadows to direct sunlight — enabling physically accurate lighting calculations, tone mapping to different display conditions, and post-capture exposure adjustment without the clipping artifacts inherent in 8-bit formats. One advantage is the format's foundational role in HDR imaging: Radiance HDR pioneered the concept of storing real-world luminance values in image files, and the .hdr format became the standard for light probe images and environment maps used in image-based lighting across the 3D rendering industry. The format's compact encoding is another practical strength — the RGBE scheme provides far more dynamic range than 8-bit formats while using only 33% more storage per pixel, a favorable tradeoff that made HDR practical on storage-limited systems of the late 1980s. HDR files are supported by Photoshop, GIMP, ImageMagick, Blender, and all major 3D renderers.

Developer: Greg Ward Larson

Initial release: 1989

Frequently Asked Questions

Why convert FAX to HDR?

HDR is widely supported by image viewers and browsers — converting from FAX eliminates the need for fax tools.

Which viewers support HDR?

Open HDR files using Adobe Photoshop, GIMP, Luminance HDR, or Photomatix.

Will the HDR result match FAX quality?

FAX to HDR conversion is lossless for document content. Lines, text, and graphics all remain intact.

Does converting FAX to HDR cost money?

No — standard conversions cost nothing. Premium plans offer higher limits for power users.

Does the converter accept multiple uploads?

Yes — the converter handles multiple files per session. Each FAX upload converts to HDR on its own.

What platforms support this converter?

The converter works in any modern web browser — Windows, macOS, Linux, Android, iOS. No installation required.

Related Conversions

FAX to PDF

FAX to JPG

FAX to TIFF

FAX to JPEG

FAX to PNG

FAX to BMP

FAX to JP2

FAX to JIF

FAX to DXF

FAX to DOT

FAX to XPM

FAX to WBMP

FAX to GIF

FAX to TGA

FAX to SVG

FAX to PCX

FAX to ICO

FAX to CUR

FAX to PBM

FAX to PGM

FAX to PPM

FAX to WEBP

FAX to EXR

FAX to FTS

FAX to G3

FAX to HDR

FAX to HRZ

FAX to IPL

FAX to MAP

FAX to MNG

FAX to MTV

FAX to OTB

FAX to PAL

FAX to PALM

FAX to PAM

FAX to PCD

FAX to PCT

FAX to PDB

FAX to PFM

FAX to PICON

FAX to PICT

FAX to PNM

FAX to PSD

FAX to RAS

FAX to RGB

FAX to RGBA

FAX to RGBO

FAX to SGI

FAX to SUN

FAX to UYVY

FAX to VIFF

FAX to XBM

FAX to XV

FAX to XWD

FAX to YUV

FAX to JBG

FAX to JBIG

FAX to HEIC

FAX to HEIF

FAX to G4

Specific converters

JPG to HDR

PNG to HDR

JPEG to HDR

EXR to HDR

PDF to HDR

JFIF to HDR

WEBP to HDR

DOCX to HDR

PPTX to HDR

HEIC to HDR

HTML to HDR

GIF to HDR

PSD to HDR

BMP to HDR

AVIF to HDR

CR2 to HDR

DNG to HDR

TIFF to HDR

NEF to HDR

SVG to HDR

TGA to HDR

DDS to HDR

ARW to HDR

XLSX to HDR

AI to HDR

DOC to HDR

PPSX to HDR

PPT to HDR

TXT to HDR

JP2 to HDR