Extract text from Group 3 fax files (G3F)
To convert G3F fax files to another format, you need Zetafax or other Raster Image software.
To convert other file formats to the "Legacy Fax" file type, you need software like Zetafax or a similar tool.
The .g3f filename extension represents two distinct legacy formats, creating frequent confusion for users. Most commonly (approx. 70%), a .g3f file is a Group 3 Fax image created by Equisys Zetafax. These files are essentially TIFF images using CCITT Group 3 compression to store high-resolution ('Fine') fax documents. While efficient for 1990s transmission, they are essentially 'dead' files on modern systems; standard viewers like Microsoft Photos or web browsers cannot natively render the raw bitonal compression, leaving you with an unopenable icon.
Alternatively, a .g3f file may be a legacy Geotechnical Project file from the DOS versions of gINT (now owned by Bentley Systems) or a 3D data file associated with Seequent Oasis montaj. These are complex binary datasets containing borehole logs or geological grids, completely incompatible with image viewers.
For the fax variant, the most practical solution is converting to PDF for archiving or TIFF for editing. Because .g3f is often just a TIFF wrapper, generic conversion tools handle them well. For geotechnical files, standard converters will fail; you must use the original legacy software or contact Bentley support for a DOS-to-Windows project migration utility.
Convert.Guru analyzes your G3F file, detects the exact format, and lets you read the text inside.
Users also converted DGR, I3F and 19 files.
If you want to convert G3F file to JPG, PDF, PNG, GIF, BMP, TIFF, TIF, WEBP, ICO, CUR, PSD or PSB, you can use Zetafax or similar software from the "Fax Image Storage" category. In the File menu, look for Save As… or Export….
To convert RAW, PNG, AI, NEF, PSB, DNG, SVG, GIF, EPS, JPG, ARW or PDF files to G3F, try Zetafax or another comparable tool in the "Fax Image Storage" category.
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our G3F converter.