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Why convert OTB to 7Z?
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 7Z format
7Z — 7-Zip Archive
7Z is a high-compression open-source archive format created by Igor Pavlov and the 7-Zip project. It offers some of the best compression ratios available for any general-purpose archive format, supports strong AES-256 encryption, and handles files up to 16 exabytes in size. It is widely used for software distribution and personal archiving.
Common uses
- Maximum compression of software installers and releases
- Encrypted archives with AES-256 for sensitive data
- Large file archiving where size matters
- Game and application distribution on Windows
Related conversions
Other conversions available for OTB and 7Z 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.