What is the difference between HEX, RGB, HSL, and OKLCH color spaces?

HEX and RGB represent colors using red, green, and blue light channels (0-255). HSL represents hue, saturation, and lightness in a cylinder, but lacks perceptual uniformity (yellow appears much brighter than blue at 50% lightness). OKLCH is a modern, perceptually uniform color space where lightness matches human eye perception, preventing muddy gradient blending and unpredictable contrast.

What are the WCAG 2.1 color contrast requirements for AA and AAA compliance?

WCAG 2.1 requires a minimum contrast ratio of 4.5:1 for normal body text and 3:1 for large text (18pt or 14pt bold) to meet Level AA. For Level AAA enhanced compliance, normal text must meet 7:1 and large text must achieve 4.5:1.

Does Color Code upload my photos to an external server when extracting colors?

No. The Image Color Extractor runs entirely in your local browser using HTML5 Canvas and Web APIs. Your images and extracted pixel data never leave your computer.

What are the standard color harmonies used in web design?

Key color harmonies include: Complementary (two colors directly opposite at 180° on the color wheel), Analogous (adjacent colors spaced 30° apart), Triadic (three colors equally spaced at 120°), Split-Complementary (a base color plus two colors adjacent to its complement at 150° and 210°), and Tetradic (four colors in two complementary pairs at 90° intervals).

How does the Color Blindness Simulator calculate color deficiency filters?

Our simulator applies scientifically calibrated Brettel and Machado matrix transformations to simulate Protanopia (red-blind), Deuteranopia (green-blind), Tritanopia (blue-blind), and total Achromatopsia, enabling designers to verify visual accessibility before publishing.

How do I export colors to Tailwind CSS or CSS Custom Properties?

Every tool on Color Code includes instant copy buttons for CSS variables (--color-primary: #hex), Tailwind class names, JSON token dictionaries, and SVG palettes.

Guides & Documentation

Color Guides & Best Practices

Everything you need to master digital color spaces, contrast compliance, and harmonic design systems for modern web apps.

Color Theory•6 min read

A Practical Guide to Color Theory & Harmonies for Digital Designers

Understand complementary, analogous, triadic, and monochromatic harmonies—and how to apply them directly into real-world UI design systems.

Read Full Guide

Accessibility•7 min read

Demystifying WCAG 2.1 Contrast: Making Web Apps Accessible to Everyone

Learn how the Web Content Accessibility Guidelines calculate contrast ratios, why AA compliance matters for legal and user experience reasons, and practical tips to pass every test.

Read Full Guide

CSS & Web•8 min read

From HEX to OKLCH: The Evolution of Color on the Modern Web

Why traditional sRGB and HSL spaces fail in modern browser design systems, and how OKLCH brings perceptual uniformity and wider gamuts to CSS Color 4.

Read Full Guide

Design Systems•7 min read

How to Build Predictable, Scalable Color Palettes for Design Systems

Step-by-step strategy for crafting systematic 50–950 shade scales, semantic color tokens, and robust theme architectures.

Read Full Guide

Quick Rules of Thumb

The 60-30-10 Rule

60% dominant neutral background, 30% structural secondary color, and 10% vivid accent color for key call-to-actions.

4.5:1 Minimum Contrast

Always maintain at least 4.5:1 contrast ratio for normal body text against backgrounds to pass WCAG AA standards.

Color Blindness Awareness

Approximately 8% of men and 0.5% of women experience color vision deficiency. Never rely solely on color to convey critical error or status information.

Semantic Color Tokens

Define functional tokens like brand-primary, surface-neutral, and status-danger instead of hardcoding raw hex values in components.