Colors Picker for Linux / Picket

• GPick

see also

• Color Name & Hue - enter RGB (Red-Green-Blue) values, HSB (Hue-Saturation-Brightness) numbers or a hexadecimal code for a color, to find its closest match of a named color and its corresponding hue.
• paletton.com - pick colors & complement - hex #AA1334 / rgb(1,2,3) / rgba(1,2,3,0)