ColorsMine

#9CA3AF on white

Tailwind gray-400 — roughly Blue Fog — measured against white to WCAG 2.2 and APCA.

2.54:1

contrast ratio · APCA Lc 47

The quick brown fox
…and the same at 13 px
✕ Body text (AA, 4.5:1) ✕ Body text (AAA, 7:1) ✕ Large text (AA, 3:1) ✕ Borders and icons (1.4.11, 3:1)

The nearest colour that passes

Keeping the hue and moving only the lightness, #707682 is the closest shade to #9CA3AF that clears 4.5:1 on white — at 4.56:1.

#9CA3AF
2.54:1 — fails
#707682
4.56:1 — passes

Under colour blindness

Contrast is a lightness relationship, so a ratio survives colour blindness — but the pair can still lose the distinction it was carrying. This is the same two colours as seen with each dichromacy.

VisionForegroundBackgroundRatio
Normal #9CA3AF #FFFFFF 2.54:1
Protanopia
red-blind, ~1% of men
#9F9FAC #FFFFFF 2.62:1
Deuteranopia
green-blind, ~6% of men
#9F9EAC #FFFFFF 2.64:1
Tritanopia
blue-blind, rare
#9CAAA9 #FFFFFF 2.40:1

What the thresholds mean

Related

Same colour on black The full gray scale

Fixing one pair is not the job

ColorsMine checks every pairing a palette implies, in light and dark, and names the single change that moves the grade most.

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