RGB input can be assigned by setting the format option to rgb.

RGBA input can be assigned by setting the format option to rgb and opacity option to true.

Opacity can be assigned by including the data-opacity attribute or by setting the opacity option to true.

CSS-wide keywords can be assigned by setting the keywords option to a comma-separated list of valid keywords: transparent, initial, inherit.

This field has a default value assigned to it, so it will never be empty.

This field will always be uppercase.

Example using Bootstrap's input groups.

Input group example with addon.

Example with swatches.

Example with swatches and opacity.