OTB to AVIF Converter
Processing entirely on your device — large files may take a moment.
Nokia OTA Bitmap and AVIF Image exist for different jobs: OTB is the Nokia OTA Bitmap — 1-bit monochrome images that old Nokia phones displayed as operator logos and picture messages. AVIF delivers the smallest files at top visual quality for modern websites — it is supported by all current browsers.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How to convert OTB to AVIF
- 1
Select your files
Drag & drop your OTB files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to AVIF". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted AVIF file individually, or grab everything at once as a ZIP archive.
About the OTB format
The Nokia OTA Bitmap coder of the ImageMagick set — the retro-phone format is written natively by the magick.wasm engine, entirely in your browser.
Obscure coder formats like this are exactly what template-driven converters list and never actually convert — here it really works.
+Strengths
- ✓Written natively by ImageMagick
- ✓Runs entirely in your browser
- ✓Free, private, no watermarks
!Limitations
- −Niche format — few modern readers
- −Feature subset varies by coder
- −Keep the original for re-editing
About the AVIF format
AVIF wraps AV1 intra-frame coding inside a HEIF container, championed by Netflix and the Alliance for Open Media. It is currently the compression king of still images: at typical web sizes it beats JPG and WebP visibly, it inherits 10/12-bit color, HDR and wide gamut from its video heritage, and it animates. Being AV1-based, it is royalty-free.
The trade-off is encoding cost: AVIF encoding is genuinely slow in software, which matters for build pipelines and batch jobs. Support is solid in every current browser (Safari since 16.4, Chrome since 85), while many native apps and older photo tools still shrug at it.
+Strengths
- ✓Best-in-class compression at web sizes
- ✓HDR, 10/12-bit color and wide gamut supported
- ✓Royalty-free (AV1) and animation-capable
!Limitations
- −Encoding is slow, especially in software
- −Native app and photo-tool support still maturing
- −No progressive decoding
Why convert OTB to AVIF?
There is a concrete reason this conversion exists: Niche format — few modern readers AVIF sidesteps that — Best-in-class compression at web sizes If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this OTB to AVIF converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Will converting OTB to AVIF reduce quality?
AVIF uses lossy compression, so a small amount of recompression is unavoidable. The quality slider lets you choose between maximum fidelity and smallest file size — the default is visually indistinguishable for photos.
What happens to EXIF data and other metadata?
Conversions here re-encode the image, and re-encoding generally does not carry the original metadata over. If the EXIF data of your OTB files matters (camera model, GPS, timestamps), keep the original file as the master and treat the converted copy as the shareable version.
Will transparent areas survive the conversion to AVIF?
Transparency is kept whenever AVIF actually supports an alpha channel. If the target format has none (like JPG), transparent areas are flattened onto a white background — that is a property of the format, not of this tool.