カラーコントラストチェッカー

前景色と背景色のWCAGコントラスト比を検査。

前景色

背景色

The quick brown fox jumps over the lazy dog

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21: 1

Contrast Ratio

WCAG AA

✓ Normal (≥4.5)✓ Large (≥3.0)

WCAG AAA

✓ Normal (≥7.0)✓ Large (≥4.5)

How to Use

1
Enter the foreground (text) color and the background color as HEX values or use the color pickers.
2
View the calculated contrast ratio and whether it passes WCAG AA and AAA standards.
3
Adjust colors until the desired accessibility level is achieved.

Calculates contrast ratios using the official WCAG 2.0 relative luminance formula.

Shows pass or fail for both WCAG AA (4.5:1) and AAA (7:1) levels for normal and large text.

Use the visual color picker or enter HEX values to set foreground and background colors.

See a live text preview rendered with your chosen colors to visualize the actual contrast.

AAは通常テスト4.5:1、大テキスト3:1。AAAは通常7:1、大テキスト4.5:1。

WCAG 2.0相対輝度計算式で人間の色覚を考慮して計算。