FAX to VIFF — Format Comparison & Online Converter
Fast, instant FAX to VIFF conversion. No signup required. Just drop your .fax file and get .viff in seconds.
Batch Settings
About FAX to VIFF Conversion
FAX and VIFF are both image formats, but they differ in important ways. FAX is a widely used file format. VIFF is a widely used file format.
When you convert FAX to VIFF, the goal is to convert between formats quickly. Converting FAX to VIFF maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your FAX file is decoded and re-encoded as VIFF. The conversion involves 4 steps: (1) your fax file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in viff 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 VIFF file. For the opposite direction, CocoConvert also supports VIFF to FAX conversion.
How to Convert FAX to VIFF
- 1
Upload .fax file
Select your FAX file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .viff
Set VIFF as the output format. The converter uses optimal settings based on the FAX→VIFF conversion profile.
- 3
Convert
The server-side engine decodes your FAX file and re-encodes it as VIFF. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .viff file. Multiple output files can be downloaded together.
What Happens When You Convert FAX to VIFF
Your FAX file is decoded and re-encoded as VIFF.
Your FAX file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in VIFF format
The converted file is ready for download
Format Comparison
FAX
.fax file
| Extension | .fax |
| MIME Type | image/g3fax |
| Category | Image |
VIFF
.viff file
| Extension | .viff |
| MIME Type | image/x-viff |
| Category | Image |
Should You Convert FAX to VIFF?
When to Convert
- ✓When you need a VIFF file
Frequently Asked Questions
What is the difference between FAX and VIFF?
FAX is a widely used file format. VIFF is a widely used file format.
Does FAX to VIFF conversion affect quality?
Converting FAX to VIFF maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, FAX or VIFF?
FAX is a common image format. VIFF is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does FAX to VIFF 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 FAX or VIFF 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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