Color Contrast Checker

Check color contrast ratio for accessibility compliance. All processing happens in your browser.

Contrast AnalyzerAccessibility Node

Foreground Channel

Background Channel

Compliance Analysis Matrix

21.00:1

Normal AA

Requirement: 4.5:1

Large AA

Requirement: 3.0:1

Normal AAA

Requirement: 7.0:1

Large AAA

Requirement: 4.5:1

Spectral Distribution100% Contrast Level

Spectral VisualizerBuffer Live

Sample text

Topology: AAWeight: Ultra Black

WCAG AA: Standard digital compliance requiring 4.5:1 ratio for normal text.

WCAG AAA: Enhanced accessibility standard requiring 7.0:1 ratio for optimal reach.

Relative Luminance: Calculating L1/L2 coordinates based on spectral weighted values.

Large Scale Logic: 18pt/14pt bold text threshold for adjusted compliance targets.