OTB to PNG8 Converter
Processing entirely on your device — large files may take a moment.
Convert PNG8 files like any PNG — to JPG, WebP or full-color formats. If your files are still in OTB format, this page is the shortcut: OTB is the Nokia OTA Bitmap — 1-bit monochrome images that old Nokia phones displayed as operator logos and picture messages.
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 to convert OTB to PNG8
- 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 PNG8". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted PNG8 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 PNG8 format
PNG was created in 1996 as a free, open replacement for the patent-encumbered GIF, and it has been the reference lossless image format ever since. Pixels are compressed with the DEFLATE algorithm (the same one inside ZIP files), which reproduces the original image exactly — bit-for-bit — while supporting full 8-bit or 16-bit alpha transparency. Screenshots, logos, icons, charts and anything with text or sharp edges should live in PNG.
Because it never discards information, PNG files of photographs are several times larger than JPG — that is the price of perfection. Modern PNG encoders add filters per scanline that make screenshots and flat-color graphics compress surprisingly well. PNG also became the base of APNG, the animation extension that browsers play natively.
+Strengths
- ✓Truly lossless — every pixel survives exactly as it was
- ✓Full alpha transparency with smooth edges, not 1-bit masks
- ✓Open standard, unpatented, with excellent tooling everywhere
- ✓Ideal for text, line art and flat-color graphics — sharp edges stay sharp
!Limitations
- −Photographs become several times larger than JPG
- −Base format has no animation (that is the APNG extension)
- −16-bit or high-resolution PNGs can grow very heavy
Why convert OTB to PNG8?
Converting makes sense where the strengths of PNG8 meet what OTB cannot give you. Truly lossless — every pixel survives exactly as it was Meanwhile Niche format — few modern readers One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this OTB to PNG8 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 PNG8?
No — PNG8 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.
Will transparent areas survive the conversion to PNG8?
Transparency is kept whenever PNG8 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.
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.