ColorsMine

#CA8A04 on white

Tailwind yellow-600 — roughly Mustard — measured against white to WCAG 2.2 and APCA.

2.94:1

contrast ratio · APCA Lc 53

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, #A56700 is the closest shade to #CA8A04 that clears 4.5:1 on white — at 4.63:1.

#CA8A04
2.94:1 — fails
#A56700
4.63:1 — 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 #CA8A04 #FFFFFF 2.94:1
Protanopia
red-blind, ~1% of men
#B2B147 #FFFFFF 2.26:1
Deuteranopia
green-blind, ~6% of men
#B5BA4E #FFFFFF 2.08:1
Tritanopia
blue-blind, rare
#C75E62 #FFFFFF 4.03:1

What the thresholds mean

Related

Same colour on black The full yellow 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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