HEIC to G4 conversion is the process of transforming images stored in the High Efficiency Image Container (HEIC) format—commonly used by iPhones and modern cameras—into the G4 (Group 4) format, a bi-level (black-and-white) fax-style CCITT compression used primarily for scanned documents. This conversion typically involves color/greyscale-to-bi-level thresholding and applying CCITT Group 4 compression to produce compact monochrome images suitable for archival or fax transmission.
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Read guide →Drag your .HEIC 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.
HEIC files typically use the image/heic MIME type and are based on the HEVC codec for high-efficiency compression of color images. G4 files use the image/tiff MIME type with Group 4 Fax compression, optimized for black and white scanned documents. HEIC is commonly used in modern smartphones and cameras, while G4 remains prevalent in fax machines and document archiving systems.
The G4 (.G4) format is commonly used for image. Understanding its characteristics can be helpful when converting to or from other formats like HEIC.
While specific technical details aren't available here, G4 files generally serve the purpose of storing image effectively within their domain.
Convert your HEIC images to the G4 format effortlessly using our online converter. Designed for speed and simplicity, our tool ensures high-quality conversions without compromising your files.
HEIC is a modern image format known for high-quality color photos with efficient compression, while G4 is a monochrome image format primarily used in fax and scanning. HEIC supports rich color depth and metadata, whereas G4 focuses on black-and-white image compression optimized for text and line art. Choosing between HEIC and G4 depends on the intended use, with HEIC suited for photographic images and G4 ideal for document imaging.
Keep source HEIC file sizes under 5–15 MB for responsive single-image conversion; very large HEIC photos may require downscaling before conversion.
To preserve detail in text or line art, use adaptive thresholding or dithering instead of simple fixed-threshold binarization.
For large batches, convert to multi-page TIFF with CCITT G4 to maintain small output sizes and simplify document handling.
Limitations: G4 is strictly bi-level—photographs will lose color and continuous-tone detail; fine gradients become high-contrast.
This converter made it easy to convert my HEIC photos to G4 for archiving.
Emma R.
Photographer
The output quality is perfect for our fax document requirements.
John M.
Archivist
Fast and reliable HEIC to G4 conversion, no software needed.
Lisa K.
Office Manager
Start your free HEIC to G4 conversion now.
Drag your file here to to upload.
Up to 250MB
If you need color or grayscale preservation, choose a different target (PNG, JPEG, or TIFF with LZW) because G4 cannot store continuous-tone color.