D3.js - D3.js is a JavaScript library for manipulating documents based on data. D3 helps you bring data to life using HTML, SVG, and CSS.
Material Palette - Generate and export your Material Design color palette
Chart.js - Easy, object oriented client side graphs for designers and developers.
Color Hunt - Curated collection of beautiful colors, updated daily
Google Charts - Interactive charts for browsers and mobile devices.
Coolors.co - The super fast color schemes generator! Create, save and share perfect palettes in seconds!