I Want Hue
I WANT HUE provides a compelling UI, using sliders to guide towards a color palette. This tool displays the end color palette as HEX and RGB values, pre-formatted for either JSON or CSS for easy copy/pasting into your tool of choice. Inspired by Chroma.js and ColorBrewer.
Credit: Mathieu Jacomy
Chroma.js
CHROMA.JS color-palette helper is a go-to resource for previewing sequential color-steps and pulling the HEX codes for them. Overall, Chroma.js is an essential tool for visualizations that utilize JavaScript (click here for the full project page).
Credit: Gregor Aisch