Convert images to ICO icon files with selectable output sizes for favicons and app icons.
ICO Converter
Convert images to ICO icon files with selectable output sizes for favicons and app icons.
About the ICO converter
One selected icon size
Choose one standard icon dimension, and the worker will resize the uploaded image into that square while preserving its aspect ratio. The output ICO contains the selected PNG-encoded subimage; it is not a multi-size icon bundle.
Favicons and transparency limits
The converter is useful for quickly preparing a favicon-sized ICO from PNG, WebP, AVIF, JPG, GIF, or BMP inputs supported by the browser. Transparency can be preserved from alpha-capable inputs, but JPG sources remain opaque and the tool does not generate app icon manifests or server-side assets.
FAQ
Common questions and answers about this topic.
Are my images uploaded to a server?
No. All conversion runs entirely in your browser inside a Web Worker. Your images never leave your device.
Which icon size should I choose?
For website favicons, 32×32 px is the standard browser-tab size, while 48×48 or 64×64 also covers bookmarks and shortcuts. This tool exports one selected size per ICO file; if you need a Windows desktop icon with multiple embedded sizes, generate the required sizes separately or use a dedicated icon packaging tool.
Will transparency be preserved?
Yes. ICO files generated by this tool use 32-bit PNG-encoded subimages, fully preserving the alpha channel from PNG, WebP, or AVIF inputs. JPG inputs (which lack transparency) will produce an opaque icon — consider trimming the background first if you need transparency.