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Why convert OTB to FAX?
Fast
Your file is converted in under 30 seconds in our cloud.
Secure
Files are automatically deleted after 1 hour.
Quality preserved
Maximum quality preserved during conversion.
About the OTB format
OTB — On-the-air Bitmap (Nokia)
OTB is a monochrome bitmap format originally used by Nokia feature phones for sending and receiving images over SMS (picture messages). It was a standard format in early mobile phones of the late 1990s and 2000s for simple graphics like logos and ringtone icons.
Common uses
- Nokia mobile phone picture message images
- Converting legacy feature phone graphics
- Historical mobile messaging image recovery
- Early mobile logo and icon conversion
About the FAX format
FAX — Group 3/4 Fax Image
FAX is a generic extension used for raw CCITT Group 3 or Group 4 fax image data files. These files contain compressed monochrome page scans as transmitted by fax machines, and are typically converted to TIFF or PDF for archival and viewing.
Common uses
- Fax document archiving and recovery
- Converting raw fax streams to viewable formats
- Legal and business fax record keeping
- Processing fax server received files
Related conversions
Other conversions available for OTB and FAX files
Frequently asked questions
Is the conversion free?
Yes, basic conversion is completely free. For large volumes, check out our paid plans.
What is the maximum file size?
Free accounts can convert files up to 25 MB. Pro accounts up to 100 MB.
How long are my files kept?
Files are automatically deleted after 1 hour on the free plan, 24 hours on Pro.
What formats are supported?
We support over 200 source and target formats. See our complete formats page.