Dynapik offers a free online tool to change image types - no need to download anything. It's quick and easy to use. You can change your PBM images to ICO format. This tool works for both professionals and casual users. Convert your images to ICO in seconds.
Portable Bitmap
The lowest common denominator of image formats.
PBM (Portable Bitmap) is the simplest format in the Netpbm suite, designed to represent monochrome (black and white) images. It uses a straightforward text-based (or simple binary) encoding where '1' represents black and '0' represents white (or vice versa depending on the viewer, though standard entails 1=black). It was designed to be easily emailed and processed by simple scripts.
There are two variants: P1 (ASCII) and P4 (Binary). ASCII P1: The file is human-readable text. A grid of 0s and 1s defines the image. Binary P4: The bits are packed into bytes for efficiency. The header simply states the magic number (P1 or P4) and the dimensions. There is no compression, no index, no palette.
Invented by Jef Poskanzer in the 1980s as a way to send bitmaps via email properly. It became the foundation of the 'pbmplus' (later 'netpbm') toolkit, which provided a standard way to convert between dozens of incompatible 80s file formats.
Microsoft Icon
The standard format for icons on Microsoft Windows and the web (favicons).
The ICO format is a container for one or more images at multiple sizes and color depths. It allows a single file to store appropriate icons for different display contexts (e.g., 16x16 for menus, 256x256 for desktop). It supports transparency and, in modern versions, PNG compression.
ICO files contain a header followed by an icon directory that lists each image entry. Each entry can use either BMP (uncompressed) or PNG compression. The format supports 1, 4, 8, 16, 24, and 32-bit color depths with optional alpha channels.
Introduced with Microsoft Windows 1.0. It became the standard for website favicons with the release of Internet Explorer 5.
Experience lightning-fast image conversions with our advanced algorithms. No more waiting for your files to be uploaded before processing.
Enjoy unlimited image conversions without any hidden fees. Our service is completely free to use, with no limitations on file size or quantity.
Convert images files between over 20 formats. We support popular formats like PNG, JPG, WebP, HEIC and more.
Use Dynapik on any device with a modern browser. We support all major platforms such as Windows, macOS, Linux, Android, and iOS.
Ensure high fidelity in your conversions. Our professional-grade output is ideal for designers, marketers, and content creators.
Your files are safe with us. We focus on your privacy and security with advanced encryption and local processing.