Adobe Color CC - Generates color themes that can inspire any project.
gpick - A color picker and color scheme creation tool.
Coolors.co - The super fast color schemes generator! Create, save and share perfect palettes in seconds!
Paletton - Color Scheme Designer
iWantHue - Colors for data scientists. Generate and refine palettes of optimally distinct colors.
Just Color Picker - Free portable colour picker and colour editor for web designers, photographers, graphic designers and digital artists. Supports Windows and macOS.