ColorsMine

#22D3EE on white

Tailwind cyan-400 — roughly Aqua — measured against white to WCAG 2.2 and APCA.

1.81:1

contrast ratio · APCA Lc 32

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, #00697D is the closest shade to #22D3EE that clears 4.5:1 on white — at 6.33:1.

#22D3EE
1.81:1 — fails
#00697D
6.33:1 — 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 #22D3EE #FFFFFF 1.81:1
Protanopia
red-blind, ~1% of men
#9394E8 #FFFFFF 2.75:1
Deuteranopia
green-blind, ~6% of men
#8A7DE6 #FFFFFF 3.41:1
Tritanopia
blue-blind, rare
#3EE3E2 #FFFFFF 1.58:1

What the thresholds mean

Related

Same colour on black The full cyan 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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