Convert to FAX online

Free online converter for converting files to FAX.

How to convert files to FAX?

1
Upload your file
Click the 'Choose File' button or drag and drop your file into the upload area. Supported formats include PNG, JPG, WEBP and more.
2
Select the output format
Make sure FAX is selected as the conversion format. Adjust additional settings if needed.
3
Start the conversion process
Click the 'Convert' button and wait a few seconds. All conversions are performed on our servers.
4
Download the result
Once the process is complete, click the 'Download' button and save the file in FAX format.

Why choose our FAX converter?

We ensure quality, convenience, and support for all formats.

High-quality to FAX conversion
High-quality to FAX conversion
We guarantee precise to FAX file conversion without any loss of quality.
Support for multiple formats
Support for multiple formats
You can convert your to FAX files from over 200 different formats, including images, documents, and more.
Compatible with all devices
Compatible with all devices
Convert to FAX files from any device – whether it's a computer, tablet, or smartphone.
User-friendly interface
User-friendly interface
Our service is designed to make to FAX conversion easy for everyone in just a few simple steps.
Full data security
Full data security
All files are transmitted and stored using advanced encryption technologies.
High-speed processing
High-speed processing
Thanks to cloud technology, we ensure fast processing even for large to FAX files.

Convert to FAX: supported formats

Convert FAX to other formats

.FAX

FAX
Group 3 FAX
Data typeImage
MIME typeimage/g3fax
DeveloperITU-T (International Telecommunication Union)
Primary use casesFax document archiving, legacy fax system interoperability, legal and healthcare document exchange

What is the FAX file format?

G3 Fax is a monochrome raster image format used to store fax documents transmitted over standard telephone networks. It encodes scanned pages as compressed black-and-white bitmap data using the ITU-T T.4 standard.

FAX file characteristics

Data typeImage
MIME typeimage/g3fax
CompressionLossless
Color depth1-bit (monochrome only)
Color spaceMonochrome (black and white)
Transparency supportNo
Animation supportNo
Resolution support204×98 dpi (standard), 204×196 dpi (fine)
EXIF / Metadata supportNo
MetadataMinimal; no embedded metadata standard
Structure typeRaster image
Standard / SpecificationITU-T T.4
Typical file size5–50 KB per page depending on content density
Year introduced1980

Advantages

The FAX file format offers several advantages that make it suitable for common use cases.

  • Extremely compact file size for monochrome text documents;
  • Lossless compression preserves content exactly;
  • Open ITU-T standard with universal fax hardware support;
  • Suitable for legally recognized fax transmission records

Limitations

The FAX file format has certain limitations that may affect its use in specific scenarios.

  • Limited to two fixed resolutions;
  • 1-bit depth only;
  • No multi-page support in base format (multi-page requires TIFF/F wrapper);
  • Not suitable for photographs or graphics;
  • No ICC color profile support

Compatibility

FAX images are widely supported and can be viewed on most devices and platforms.

  • Browser support: No
  • Mobile support: No
  • Streaming support: No

Security considerations

G3 files present minimal security risk due to their simple structure and lack of scripting or executable content; malformed files may cause issues in legacy fax parsing software.

License

Open standard (ITU-T)

G3 Fax (MIME type image/g3fax) is a monochrome raster image format defined by the ITU-T T.4 standard for Group 3 facsimile transmission over the public switched telephone network (PSTN). Each file stores a single scanned page as a compressed black-and-white bitmap at a fixed resolution of 204×98 dpi (standard mode) or 204×196 dpi (fine mode). Compression is achieved using Modified Huffman (MH) encoding, a run-length coding scheme optimized for the sparse black-and-white content typical of text documents. G3 Fax does not support color, grayscale, or variable resolution beyond the two defined modes. It is primarily used for archiving and exchanging fax documents in enterprise, legal, healthcare, and government environments where fax remains a legally recognized transmission method. Modern fax software and multifunction printers continue to read and write G3 files, though the format has largely been superseded by TIFF/F and PDF in digital workflows.