Beautiful colored gradients
WebGradients is a free collection of 180 linear gradients that you can use as content backdrops in any part of your website.
Curated gradients for designers and developers
2017 Grabient by unfold
Khroma is the fastest way to discover, search, and save color combos you'll want to use.
Best Flat Colors For UI Design
Color Claim was created in 2012 by Tobias van Schneider with the goal to collect & combine unique colors for my future projects.