ICO converter
ICO is the icon format used by Windows and favicons. It stores several sizes in one file and supports transparency. The converter assembles an ICO from PNG or JPG for a website, shortcut or app.
Convert to ICO
When ICO is needed
ICO is used for favicons, Windows shortcuts and app icons. A website favicon usually needs 16×16, 32×32 and 48×48 sizes.
Which source to choose
PNG is better for a transparent background. JPG has no alpha channel, so the icon background will be opaque.
Format questions
What ICO size is needed for a favicon?
Usually 16×16, 32×32 and 48×48. For modern browsers, you can also provide a PNG or SVG.
Is transparency preserved?
With PNG input, yes. JPG does not support transparency, so the background becomes opaque.