CDT to G4 conversion is the process of transforming a CorelDRAW Template file (CDT) into a G4 fax image or graphics format typically using Group 4 (G4) bi-level compression. This conversion extracts the drawing or rasterized pages from the CDT and encodes them as G4-compressed monochrome images suitable for fax transmission, archiving, or compatibility with legacy imaging systems.
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Read guide →Drag your .CDT 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.
CDT files usually have the MIME type application/x-coreldraw and are used primarily in vector graphic creation. G4 files use the MIME type image/g3fax or image/g4fax depending on the compression and are common in fax communication and document imaging. G4 employs CCITT Group 4 compression codec, which is lossless and 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 CDT.
While specific technical details aren't available here, G4 files generally serve the purpose of storing image effectively within their domain.
Our Online CDT to G4 Converter offers a seamless way to convert CDT files into the G4 format without software installation. Designed for professionals in the Drawing category, this tool ensures high-quality, accurate conversions accessible from any device.
CDT files are typically native to CorelDRAW and store vector drawing data, making them ideal for detailed graphics editing. In contrast, G4 is a fax-compatible bitmap image format optimized for compression and transmission. While CDT files focus on design flexibility, G4 files emphasize compactness and compatibility with document scanning and faxing.
Keep source CDT file sizes under 50–100 MB for fastest, most reliable web conversions; very large files with many embedded high-resolution images can slow or fail the process.
To preserve legibility, rasterize at 300 DPI for text and detailed line art before G4 encoding; use 600 DPI only if the receiving system requires very fine detail.
When converting color CDT artwork to G4, apply proper thresholding or error-diffusion dithering to retain visual contrast; preview results and adjust settings rather than relying on defaults.
For batch conversion, group similar DPI and threshold settings together (e.g., all text-heavy templates at 300 DPI) to maintain consistent output and reduce processing time.
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Emily R.
Graphic Designer
The quality of G4 files after conversion is excellent and reliable.
Mark L.
Architect
Easy to use and perfect for integrating drawing files into our document workflows.
Sophia M.
Project Manager
Start your free CDT to G4 conversion now.
Drag your file here to to upload.
Up to 250MB
Format limitation: G4 is a bi-level (black-and-white) compression designed for fax/archival; it cannot store color or grayscale natively, so color gradients and subtle tones will be reduced to two levels.