Based on a list of colors you can update (in a Javascript table embedded), this page shows the level of accessibility (WCAG 2.0 AA or AAA levels) for all combinations (text/background/font-size).
https://uid.1aipp.com/WCAG_color_matrix
To personalize this matrix, please edit "colors.js" and replace existing colors with yours (you can add as many colors as needed):
var colors = ["#0D0D0D","#1A1A1A","#262626","#333333","#454545","#6D6D6D","#959595","#BDBDBD","#DCDCDC","#E9E9E9","#F7F7F7","#FFFFFF","#005EB8","#00A9E0","#9BCAEB","#CE0058","#6F2B8D","#E95326","#AB5C00","#F7A827","#FEEB3D","#33D681","#00A34E","#00701B"];