Converting ICO to BMP extracts the largest icon image to uncompressed Windows bitmap data. Useful for legacy Windows software or icon-editing workflows that expect BMP source.
Drag & drop image files here, or browse
Drop your ICO files here
Lossless pixel preservation. File size grows because BMP is uncompressed. Alpha support in BMP is inconsistent; some tools honor the 32-bit BMP alpha channel, others don't.
BMP works on every Windows version and most cross-platform viewers.
ICO is the Windows icon format. A single .ico file can hold multiple resolutions (16×16, 32×32, 48×48, 256×256) and color depths simultaneously, letting the OS pick the best for context. Every browser serves favicons as ICO, and Windows desktop icons use it natively.
BMP is the uncompressed Windows bitmap format from 1990. Files are huge because almost nothing is compressed, but the format is trivial to decode and supported by virtually every Windows utility, embedded system, and legacy tool. Useful as an interchange format when other options fail.
In 32-bit BMP output, technically yes; but many tools ignore BMP alpha. For reliable transparency, use PNG.
The largest size in the ICO.
ICO is the Windows icon format. A single .ico file can hold multiple resolutions (16×16, 32×32, 48×48, 256×256) and color depths simultaneously, letting the OS pick the best for context. Every browser serves favicons as ICO, and Windows desktop icons use it natively.
BMP is the uncompressed Windows bitmap format from 1990. Files are huge because almost nothing is compressed, but the format is trivial to decode and supported by virtually every Windows utility, embedded system, and legacy tool. Useful as an interchange format when other options fail.
Yes. The converter runs entirely in your browser using WebAssembly. Your images are never uploaded, never sent to a server, and never leave your device.
There's no hard limit, but because everything runs in your browser you're bounded by available memory. Very large images (over a few hundred megapixels) can hit browser memory limits. Process in smaller batches if you run into issues.