HEIC to G3 — Format Comparison & Online Converter
Fast, instant HEIC to G3 (FAX) conversion. No signup required. Just drop your .heic file and get .g3 in seconds.
Batch Settings
About HEIC to G3 (FAX) Conversion
HEIC (introduced 2015) and G3 are both image formats, but they differ in important ways. HEIC (High Efficiency Image Container) is Apple's format for iPhone photos, offering twice the compression of JPEG. G3 is a widely used file format.
When you convert HEIC to G3, the goal is to convert between formats quickly. Converting HEIC to G3 maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your HEIC file is decoded and re-encoded as G3. The conversion involves 4 steps: (1) your heic file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in g3 format, (4) the converted file is ready for download.
CocoConvert's converter handles the entire pipeline server-side using FFmpeg, Sharp, and qpdf — battle-tested libraries used by streaming platforms and enterprise tools. Files are encrypted in transit and deleted within 24 hours.
This conversion is ideal when you When you need a G3 file. For the opposite direction, CocoConvert also supports G3 to HEIC conversion.
How to Convert HEIC to G3 (FAX)
- 1
Upload .heic file
Select your HEIC file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .g3
Set G3 as the output format. The converter uses optimal settings based on the HEIC→G3 conversion profile.
- 3
Convert
The server-side engine decodes your HEIC file and re-encodes it as G3. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .g3 file. Multiple output files can be downloaded together.
What Happens When You Convert HEIC to G3 (FAX)
Your HEIC file is decoded and re-encoded as G3.
Your HEIC file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in G3 format
The converted file is ready for download
Format Comparison
HEIC
.heic file
| Extension | .heic |
| MIME Type | image/heic |
| Category | Image |
G3 (FAX)
.g3 file
| Extension | .g3 |
| MIME Type | image/g3fax |
| Category | Image |
Should You Convert HEIC to G3 (FAX)?
When to Convert
- ✓When you need a G3 file
Frequently Asked Questions
What is the difference between HEIC and G3?
HEIC (High Efficiency Image Container) is Apple's format for iPhone photos, offering twice the compression of JPEG. G3 is a widely used file format.
Does HEIC to G3 conversion affect quality?
Converting HEIC to G3 maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, HEIC or G3?
HEIC uses lossy compression. G3 is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does HEIC to G3 conversion take?
Most conversions finish in seconds. Larger files or complex image content may take 10–30 seconds. CocoConvert processes files in parallel for batch jobs.
Is HEIC or G3 better for long-term storage?
Both formats use lossy compression, so consider keeping your original source file for long-term storage.
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