FAX to G4 Converter

FAX to G4 — fax image conversion online free

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Fast Turnaround

Most FAX to G4 conversions complete within seconds. Optimized cloud servers process files efficiently.

File Safety First

All uploaded FAX data is deleted post-conversion. G4 files are cleaned from servers within 24 hours.

Fax Digitization

Transform legacy FAX images into modern G4 format — making archived fax content digitally accessible.

How to convert FAX to G4

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

Choose g4 or any other format you need as a result (more than 200 formats supported)

Let the file convert and you can download your g4 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

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

Frequently Asked Questions

Why convert FAX to G4?

Different fax systems use different formats. Converting FAX to G4 ensures compatibility with specific fax workflows.

What tools read G4 files?

G4 files can be opened with fax software, IrfanView, or document archival systems.

Are all details preserved in the G4 output?

Every detail in your FAX file carries over to G4. The conversion preserves sharpness and readability.

Is the online FAX to G4 converter free?

Standard FAX to G4 conversion is free. Premium tiers exist for heavy users needing more throughput.

Can I upload a batch of FAX files?

Upload a batch of FAX files and each will be independently converted to G4 — all downloadable separately.

Do I need to install any software?

No installations needed. The FAX to G4 conversion runs entirely in your browser — nothing to download or set up.

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FAX to BMP

FAX to JP2

FAX to JIF

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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

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FAX to JBG

FAX to JBIG

FAX to HEIC

FAX to HEIF

FAX to G4

Specific converters

JPG to G4

PNG to G4

PDF to G4

JPEG to G4

PPTX to G4

TIFF to G4

HTML to G4

GIF to G4

DOCX to G4

JFIF to G4

SVG to G4

XLSX to G4

TXT to G4

WEBP to G4

ICO to G4

PPSX to G4

PGX to G4

PS to G4

HEIC to G4

XLS to G4

G3 to G4

DOC to G4

CR2 to G4

CDR to G4

BMP to G4

ABW to G4

DBK to G4

KWD to G4

SXW to G4

AW to G4