OTB to XBM Converter
Processing entirely on your device — large files may take a moment.
Nokia OTA Bitmap and X BitMap 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. Convert XBM icons to PNG for viewing, or emit XBM when embedded firmware/Unix code needs a compiled-in bitmap.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How OTB compares to XBM
| OTB | XBM | |
|---|---|---|
| Structure | Nokia OTA Bitmap coder | C #defines + hex byte array |
| Compatibility | ImageMagick, specialty tools | X11, C compilers, GTK |
| Best for | Legacy and specialty pipelines | Compiled-in cursors and icons |
How to convert OTB to XBM
- 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 XBM". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted XBM 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 XBM format
XBM is the most honest image format ever shipped: the "file" is a C source array of hex bytes, compiled straight into X11 applications as cursor and icon bitmaps. Rendered, it is 1-bit black and white — the ancestors of every pixel-art cursor you still use.
Because it compiles, XBM never died: firmware UIs, embedded icons and retro Unix tooling still want it. Converting a PNG down to XBM gives embeddable, compilable art; the other direction previews what the C array actually draws.
+Strengths
- ✓Compiles directly into C/C++ programs
- ✓Zero-payload format — text only
- ✓Still required by embedded and Unix tooling
!Limitations
- −1-bit black & white only
- −Human-hostile representation
- −X11 bit order trips up hand-rolled decoders
Why convert OTB to XBM?
Think of it as moving your file to the container that fits the job. Niche format — few modern readers XBM works differently: Compiles directly into C/C++ programs If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.
Frequently asked questions
Is this OTB to XBM 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 I lose quality converting OTB to XBM?
No — XBM is a lossless format, so every pixel of the converted image matches your original OTB file. You can also adjust the quality/size balance before converting when the target format supports compression.
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 XBM?
Transparency is kept whenever XBM 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.