How your colorblind and colorweak readers see your colors - Datawrapper Blog
Colors
ColorBrewer: Color Advice for Maps
ColorBrewer Palettes Sketch Freebie
Color Oracle | Color Oracle
Tanaguru Contrast-Finder
Pika • Super High Fives
Contrast Ratio - WCAG Color Contrast Checker
Color and Contrast.com
WebAIM: Contrast and Color Accessibility - Understanding WCAG 2 Contrast and Color Requirements
WhoCanUse
A tool that brings attention and understanding to how color contrast can affect people with different visual impairments.
WebAIM: Contrast Checker
Contrast tools
Color Safe - accessible web color combinations
Accessible color palette builder
Using color
Randoma11y - Accessible color combinations
Designing accessible color systems
Orange You Accessible? A Mini Case Study on Color Ratio | Bounteous