How to convert BMP to ICO
- Drop your BMP files on the box above, or click it to choose them (up to 30 at once).
- Press Convert. Each file is processed on your device and shows its old and new size.
- Download the files one by one or take them all as a ZIP.
What changes when you convert BMP to ICO
- Every decoded pixel is written exactly — ICO is lossless here.
- BMP images have no transparency, so there is nothing to lose there.
- Camera details and GPS location (EXIF) are not copied into the new file. Photo orientation is applied to the pixels first, so the result is the right way up.
- The icon contains six sizes — 16, 32, 48, 64, 128 and 256 pixels. A non-square picture is centred with transparent padding rather than stretched.
About BMP and ICO files
BMP is the old Windows bitmap format. It stores every pixel uncompressed, so files are very large, but almost any program — including very old ones — can read it.
An ICO file holds the same picture at several sizes so Windows and browsers can pick the right one. Here each size is stored as a PNG inside the icon, which Windows Vista and later and every current browser read. It is a good choice for website favicons and Windows shortcut or folder icons.
Limits
Up to 30 files of 25 MB each per batch and images up to 50 megapixels — beyond that browsers run out of memory, so the tool says so instead of producing a broken file. Files that are not images, or are damaged, are rejected with the reason.