CFF to G4 conversion is the process of transforming a file in the CFF (Compact Fax Format) container into the G4 (Group 4 fax encoding) raster format. This conversion repackages or re-encodes black-and-white scanned pages from CFF’s variant structure into the standardized, highly compressed G4 bitonal image stream commonly used for fax and archival TIFF files.
Related guides
Practical guides to help you choose formats, preserve quality, and avoid common conversion problems.
WebP has quietly become the default image format of the modern web, delivering 25-35% smaller files than JPG and PNG with universal browser support. This 2026 guide covers current adoption stats, browser compatibility, WordPress integration, conversion workflows, and when to choose WebP over AVIF for optimal Core Web Vitals performance.
Read guide →Not sure whether to save your image as PNG or JPG? This detailed comparison covers compression, transparency, file size, web performance, and real-world use cases so you can pick the right format every time — with conversion links when you need to switch.
Read guide →Learn how to convert HEIC to JPG for maximum compatibility. This guide explains what HEIC is, why iPhones use it, the key differences between HEIC and JPG, and walks through every conversion method including online tools, iPhone settings, Windows, and Mac.
Read guide →Drag your .CFF file from your computer or use the browse function.
Confirm .g4 as the selected destination format.
Click "Convert" and download your converted .G4 file once ready.
CFF files usually have the MIME type application/vnd.cff and are used in niche applications for font or graphic formats. G4 files often use the MIME type image/g4 and are commonly associated with fax and scanned image compression. The G4 format employs CCITT Group 4 compression, which is highly efficient for monochrome images.
The G4 (.G4) format is commonly used for image. Understanding its characteristics can be helpful when converting to or from other formats like CFF.
While specific technical details aren't available here, G4 files generally serve the purpose of storing image effectively within their domain.
Easily convert your CFF files to G4 format using our online CFF to G4 converter. Designed for quick and accurate conversion, our tool supports seamless file processing without the need for complicated software downloads.
CFF files are typically used for specialized purposes with limited device support, while G4 format is widely accepted and optimized for compression efficiency. G4 tends to have smaller file sizes making it more practical for sharing and archiving compared to CFF.
Keep source files under 50–100 MB per document for fastest browser-based conversion; large multi-page archives perform better when split into chunks.
To preserve legibility, ensure source CFF is true 1-bit (bitonal) or high-contrast grayscale before converting; applying thresholding prior to conversion improves G4 results.
For batches, convert CFF files in groups rather than all at once; use a command-line or desktop tool for bulk jobs to avoid timeouts and keep consistent settings.
Format limitation: G4 is strictly a bi-level (black-and-white) encoding—continuous-tone grayscale or color data in CFF must be dithered or thresholded, which can reduce visual fidelity.
This CFF to G4 converter saved me hours by simplifying the format switch.
Emily R.
Graphic Designer
Reliable and fast tool for converting CFF files online without errors.
John M.
IT Specialist
Great compression results with no quality loss after converting to G4.
Lisa K.
Photographer
Start your free CFF to G4 conversion now.
Drag your file here to to upload.
Up to 250MB
If you need searchable text, perform OCR on the CFF source before or after conversion; G4 stores only image data and cannot embed selectable text.