Convert BMP files to ICO free in your browser — no signup, no install, and the file is never uploaded to a server. ICO keeps full quality with no further loss.
Add your BMP file
Drag the BMP file onto the drop area above, or click it to pick a file from your device. You can add several files at once.
Confirm ICO as the output
ICO is already selected as the output format on this page. You can set the output width and height. Quality stays untouched because this format is lossless.
Run the conversion
Press the convert button. A single image is usually done before you finish reading this sentence.
Download the ICO file
When it finishes, download the ICO file. Converting multiple files gives you the option to download them together as a ZIP.
A Windows standard format that stores pixel data with little or no compression. There is no quality loss, but files are very large.
The format used for Windows icons and website favicons, capable of holding several sizes from 16x16 up to 256x256 inside a single file.
Yes. BMP to ICO conversion is completely free with no signup, no watermark, and no daily limit on the free plan for ordinary use.
No. The conversion runs entirely inside your browser using WebAssembly, so the BMP file never leaves your device. That is also why it works without an internet connection once the page has loaded.
It can go either way. Both formats are lossless, so nothing is thrown away — the size difference comes from how each one packs the same data.
The free plan handles files up to 200MB. Because processing happens on your own device, very large files depend on your computer's memory rather than a server quota.
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What each file format is, what it is used for, and which formats it can be converted to.
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