Images
What is a WBMP file?
Updated Jul 2026
WBMP (Wireless Bitmap) is a black and white image format built for early mobile phones browsing the WAP web in the late 1990s and early 2000s. Every pixel is stored as either on or off, with no gray, no color, and no compression beyond that. It's lossless but limited to simple 1-bit graphics like icons and logos.
- Extension
- .wbmp
- Type
- Images
- Typically
- Legacy mobile
- Transparency
- None
Why WBMP exists
WBMP was designed for a time when mobile phones had tiny screens, little memory, and slow data connections. Carriers used WAP (Wireless Application Protocol) to serve stripped-down web pages to feature phones, and WBMP was the image format that came with it, built to be as small and simple as possible.
The format stores an image as a plain grid of black and white pixels, one bit each. There's no color palette, no grayscale, and no compression trick beyond that bare bit-per-pixel structure. That makes WBMP files tiny and quick to decode, which is exactly what a low-powered phone from that era needed.
You mostly run into WBMP now through old software, legacy WAP sites still limping along, or Java ME and older mobile development tools that used it for icons and simple graphics. Modern devices, browsers, and photo apps don't handle it, so anyone who opens one today usually needs to convert it to something like PNG first.
The trade-offs
Strengths
- Extremely small file size
- Simple format that's fast to decode
- Lossless within its 1-bit black and white limits
Watch-outs
- No color or grayscale, only black and white pixels
- Not supported by modern browsers, phones, or photo apps
- Poor fit for anything beyond simple icons or line art
- Needs converting before you can view or edit it on current devices
A note on privacy
A WBMP file is just a grid of black and white pixels, so it carries no EXIF data, GPS location, or camera details to worry about. Still, if the file came off an old device or archive you'd rather not upload anywhere, an online converter still means sending it to someone else's server. Converting it on your own computer keeps it there the whole time.
Questions
How do I open a WBMP file?
Most current operating systems and browsers don't open WBMP directly. The simplest path is converting it to PNG or JPG, which any modern app or device can display.
Is WBMP better than PNG?
Not for anything beyond a tiny black and white icon. PNG supports full color, grayscale, and transparency, while WBMP is stuck at 1-bit black and white. WBMP files are smaller, but PNG is what everything actually supports today.
Why do I have a WBMP file at all?
It usually comes from an old WAP-era phone, legacy mobile software, or a Java ME project that generated icons in this format. It's rare to encounter one from anything made in the last decade or so.
Can I convert WBMP without uploading it?
Yes. A desktop app like Morphjet converts WBMP to PNG or JPG right on your own computer, so the file never has to leave your machine.
Morphjet opens and converts WBMP and 1,800+ other formats, all on your own computer. Launching this July.