What is the best color and alpha for icon? about material-design-icons HOT 1 CLOSED

Hi Henry,
This isn't much a bug – but more of a question isn't it ;-) Happy to help though...

You should consider the material design spec as the correct authority, if you're building an app using material design. I expect we'll bring the Android guidelines in-line with it in the future.

The icons are correct and in-line with the material design spec.
We've included black, white, and grey600 colors of the icons. They grey600 icons are included as a convenience for use on white backgrounds. You should not use them on non-white backgrounds.

On light backgrounds, you should use the black icon with opacity 54% (or 26% if disabled)
On dark backgrounds, you should use the white icon with opacity 100% (or 30% if disabled)

As for using colored icons, you should do so at 100% opacity, and be sure that your icon provides an adequate contrast to the background, both for general usability and also for accessibility.

For colored backgrounds, use either white or black, depending on which provides a greater degree of contrast and using the opacity values mentioned above.

Hope that helps.

from material-design-icons.