WebGradients
Free Gradients Collection: Sketch/Photoshop/CSS
Brand Colors
The biggest collection of official brand color codes around. Includes hex colors codes for 500+ brands including Facebook, Twitter, Instagram, and many more.
ColorHunt
Thousands of trendy color palettes in a curated collection that is updated daily. Get a fresh color palette for your next design project and save all the palettes you like.
LOLColors