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Explainers written for Color Picker by Noble Erne, LLC and reviewed before publication. Every guide carries a review date so you can tell how current it is.
HEX, RGB, HSL, CMYK: which color code to use when
Four ways to write the same color, and the one most people should be using more (it’s HSL).
5 min read · Reviewed July 2026
The 4.5:1 rule: color contrast that keeps you legal
Low-contrast text is the web’s most common accessibility failure, and since the European Accessibility Act it carries legal risk. The rules, the math, the fixes.
5 min read · Reviewed July 2026
How to build a color palette that doesn’t fight itself
The 60-30-10 rule, the color wheel relationships behind our palette generator, and why fewer colors always looks more professional.
5 min read · Reviewed July 2026
Color psychology in marketing: what’s real, what’s myth
Red does not make people hungry and blue does not make them trust you. What the research actually supports, and what to do instead of chasing color magic.
5 min read · Reviewed July 2026
Why your printed colors never match the screen
RGB is light, CMYK is ink, and the orange you love may not exist on paper. The gamut problem explained, plus how to avoid expensive surprises.
4 min read · Reviewed July 2026
Published by Noble Erne, LLC. Enterprise systems consultant with a background in SAP implementation, software documentation, and instructional design. Builds the tools and writes the explainers on this site. More about this site.