Compare Bitmap Image and Icon File formats — understand the key differences and when to use each
Bitmap Image
BMP (Bitmap Image File) is an uncompressed raster image format developed by Microsoft. BMP stores pixel data directly without compression, resulting in very large file sizes but perfect image quality with zero artifacts. The format supports 1-bit (monochrome), 4-bit (16 colors), 8-bit (256 colors), 16-bit, 24-bit, and 32-bit color depths. BMP is primarily used in Windows environments and was historically the default format for Windows Paint. While BMP offers the highest quality preservation, its lack of compression makes it impractical for web use or email. Converting BMP to PNG provides identical visual quality with dramatically smaller file sizes. BMP does not support transparency, animation, or metadata. It remains useful for certain technical applications and as an intermediate format in image processing pipelines.
Icon File
ICO (Icon) is a file format used for icons in Microsoft Windows. ICO files can contain multiple sizes and color depths in a single file, typically including 16×16, 32×32, 48×48, and 256×256 pixel variants. The 256×256 size uses PNG compression. ICO is also used for website favicons (favicon.ico) displayed in browser tabs. Converting PNG to ICO is a common task for web developers and software creators.
| Feature | BMP | ICO |
|---|---|---|
| Full Name | Bitmap Image | Icon File |
| File Extension | .bmp | .ico |
| Category | image | image |
| Free to Convert | ✓ Yes | ✓ Yes |
| Browser Support | ✓ All Browsers | ✓ All Browsers |
| Convert to Each Other | ✓ Yes | ✓ Yes |
或将文件拖放到此处
最大文件大小：2GB