Convert SVG to ICO using ImageMagick, with transparent background and multi-size icons

svg2ico.sh

convert -density 256x256 -background transparent favicon.svg -define icon:auto-resize -colors 256 favicon.ico

The icon can also be colored:

convert -density 384 -background transparent -fill "#607D8B" -colorize 100 favicon.svg -define icon:auto-resize -colors 256 favicon.ico

For anyone else wondering why the density must be set

@mjhasbach @azam @keith24 I'm still getting blurry images with this. Is there an icon:auto-density ?

@graingert I got better results by using -density 256x256 as specified in this SO answer.

So to sumarize, use:

convert -density 256x256 -background transparent favicon.svg -define icon:auto-resize -colors 256 favicon.ico

This can be done in magick directly:

magick -density 256x256 -background transparent favicon.svg -define icon:auto-resize -colors 256 favicon.ico

Updated with latest working parameters. Thanks all !

Hi there, I'm jumping into this thread long after the previous post... But this command gives me a multi-sized ICO as expected, but all dimensions are completely white (or any color I specify as the background parameter)... I don't find any clue about it for now...

If you want your favicon contain only certain sizes, you can specify them by setting `icon:auto-resize=64,48,32,16". This will lead to a much smaller file.

Full command:

convert -density 256x256 -background transparent favicon.svg -define icon:auto-resize=64,48,32,16 -colors 256 favicon.ico

My .ico also has white background when using this command:
magick favicon.svg -density 256x256 -background transparent -colors 256 -define icon:auto-resize="128,64,48,32,16" favicon.ico

What I'm doing wrong?

@GarfieldDeepClone it could be that your source SVG has white background

is anyone else noticing that the icon size is always ~300kb when using imagemagick? This seems a bit excessive.

I ran into the same problem as @pa-0 described but managed to decrease the file size by defining the sizes i want to have like @gsilvan pointed out.

@GarfieldDeepClone it could be that your source SVG has white background

I have the same problem, and the SVG has a transparent background. (It was generated by InkScape's "Save as plain SVG" and I tested it with different backgrounds to confirm that the background is transparent.)