Color

Adobe Color

Create or browse colour schemes

Color Hunt

Color Palettes for Designers and Artists

Color Tool

Create and share colour palettes for your UI

ColorBox

A colour tool to produce colour sets

Colour Contrast Analyser

Determine the legibility of text and the contrast of visual elements

Grabient

Beautiful and simple UI for generating web gradients

Happy Hues

Curated colors in context

Material Theme Builder

Visualize dynamic color

Color - iOS

Colour guidelines for iOS

Color meanings

Color meanings and symbolism

Color - UWP

Colour guidelines for UWP apps

The color system

The Material Design colour system