Some tools that make our life easier when working with Color. Choosing, composing, comparing, refining color palettes or testing them for Accessibility.
What used to be Kuler, now Color CC. Probably the most complete of all, quite technical and less "intuitive", requires some basic knowledge of Color Theory (which on the other hand, we should all have) to fully take advantage of it. It also allows to import an image to extract its values and that, sometimes, is very very useful.
Galen Gidman's side project already compiles the color palettes of more than 600 brands of all types. Fantastic to choose, try, compare and see where the brands in this field move.
How to test if your color palette meets web accessibility standards? This, by Brent Jackson, makes it really easy for you. Something basic, is still useful as a reference tool.
Tobias Van Schneider published a couple of years ago his "Color Claim", where he collects more than a hundred color combinations, developed by himself, presented really well and also offers download of the full palette for Sketch or Adobe CC.
As Gal Shir details in his description, it is an "open platform to facilitate inspiration with thousands of handmade pallets". Little more to add, particularly interesting to be able to search for recent, popular or "trendy", in addition to participating creating palettes or voting existing ones. Really great.
Probably this, by Fabrizio Bianchi, is the one that we use the most, it helps to create your own palettes with the generator, full of with different options to fine tune it, according to your needs. It also has an "Explore" section, where you can see the palettes shared by users, an iOS app (Android app, please!) and Adobe CC integration.
This tool extracts the color palettes of the most upvoted products in Product Hunt in a very visual way and also allows you to filter by themes, which makes it easier to see the chromatic tendencies in each category. Neat.
A specific one for gradients, from the people at Unfold, allows not only to consult but also to modify the existing gradients to your liking, and then download and use them in Sketch, easily.
Another great one for testing accessibility issues. Technically based on Colorable, previously mentioned, the interface is much more pleasant and allows to test systems, not only fast combinations, adding more references. Made by the The Scenery team.
Collection of 180 linear gradients by itmeo, with CSS code available and a downloadable PNG of each sample, as well as .sketch and .PSD.
In addition to these, we use some more sporadically, but their functions are overridden by the mentioned ones or are more specific / not so useful in a generic way. We'll keep updating this list, stay tuned!