ConvertICO is a free. It is fast, free and easy to use. It is used to , App Icons as well as the much needed favicons for websites. Go ahead and give it a try, you will be pleased.
iConvert Icons v3.0for Windows, Mac OS X, Linux, iOS, and Android.
ICO converter is a simple. It will take any image and convert it to ICO file, for web site favicon or Windows applications.
Converticon is a simple icon utility. It can import ICO, PNG, GIF, and JPEG formats and export to high-quality PNG or ICO files. There is no software to download and it’s 100% free.