G4 to EXR Converter

Convert G4 files to EXR — instant online tool

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Server-Side Engine

All processing happens in the cloud. Your computer stays free while G4 converts to EXR on our servers.

Legacy Format Bridge

G4 is a legacy format. Converting to EXR brings your fax archives into modern, widely accessible formats.

Safe Conversion

Your G4 file is removed right after processing. The EXR download is auto-deleted within 24 hours.

How to convert G4 to EXR

1

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

2

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

3

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

About formats

G4 is a monochrome image format based on the ITU-T Group 4 facsimile coding standard (Recommendation T.6), ratified by the CCITT in 1984 as an improvement over Group 3 for use on error-free digital networks like ISDN rather than analog telephone lines. G4 files contain 1-bit image data compressed using exclusively two-dimensional Modified Modified READ (MMR) coding, where each scanline is encoded as a set of differences (changing elements) relative to the line above it. By eliminating the one-dimensional coding fallback and the end-of-line synchronization markers required by Group 3, G4 achieves 20-50% better compression ratios on typical document pages while producing a simpler, more regular bitstream. The format is most commonly encountered as a compression method within TIFF files (TIFF compression tag 4), where it became the standard archival format for scanned documents in enterprise document management, government records, and legal imaging systems. G4 compression is specified at 200, 300, or 400 dpi depending on the scanning application, with 300 dpi being the most common for archival-quality document imaging. One advantage is exceptional compression efficiency for document content: G4's two-dimensional prediction exploits the strong vertical correlation in text and line art pages, typically compressing a 300 dpi letter-size page to 30-50 KB — roughly half the size of equivalent Group 3 encoding. The format's entrenchment in document management infrastructure is another strength — G4 TIFF is the mandated format for many government digital records systems, court filing systems, and corporate archives, supported by every enterprise imaging platform.
Developer: ITU-T (CCITT)
Initial release: 1984
EXR is a high-dynamic-range raster image format developed by Industrial Light & Magic (ILM) internally since 1999 and publicly released as open-source software in January 2003. OpenEXR was created to meet the demanding requirements of feature film visual effects compositing, where scenes routinely contain extreme brightness ranges — from deep shadows to specular highlights on water, metal, or light sources — that exceed the precision of 8-bit or 16-bit integer formats. EXR stores pixel data in 16-bit floating-point (half) or 32-bit floating-point per channel, providing over 30 stops of dynamic range with smooth precision across the entire luminance spectrum. The format supports an arbitrary number of channels (not just RGBA), tiled and scanline storage, multiple compression methods (lossless ZIP, lossy B44 and DWAA/DWAB for preview quality), multi-part files containing multiple views or layers, and deep pixel data where each pixel stores multiple depth-sorted samples for volumetric effects. One advantage is compositing fidelity: the floating-point precision means that color grading, exposure adjustments, lighting changes, and multi-layer compositing operations produce mathematically correct results without the banding, clipping, or quantization artifacts inherent in integer formats. EXR's adoption as the VFX industry standard is another core strength — it is the default interchange format for Foundry Nuke, Autodesk Flame, Blackmagic Fusion, Adobe After Effects, and every major 3D renderer, and its open-source C++ library is embedded in hundreds of production tools.
Initial release: January 2003

Frequently Asked Questions

Why convert G4 to EXR?

EXR is widely supported by image viewers and browsers — converting from G4 eliminates the need for fax tools.

Which apps open EXR files?

Open EXR files using Adobe Photoshop, GIMP, Blender, or Nuke.

Is the converted EXR file high quality?

Document content stays crisp and readable. The converter maintains G4 image fidelity in the EXR result.

Do I need to pay for this conversion?

No cost for standard G4 to EXR conversions. Premium plans add faster processing and increased file limits.

Does this tool handle multiple files?

Yes — batch upload is supported. Drop multiple G4 files and each one converts to EXR for separate download.

Can I use this converter on a Mac?

Yes — the converter runs in any browser on macOS, Windows, Linux, Android, and iOS. Fully cross-platform.