#517a8d on #000000 contrast ratio
4.51:1
Blue text (#517a8d) on a black background (#000000) meets WCAG 2.2 level AA for normal text. It passes 4 of 5 checks below.
Swap: #000000 on #517a8dLarge text sample
Normal body text in #517a8d on #000000. The quick brown fox jumps over the lazy dog.
WCAG 2.2 results
| Normal text — WCAG 1.4.3 AA | 4.5:1 | Pass |
|---|---|---|
| Large text — WCAG 1.4.3 AA | 3:1 | Pass |
| UI components & icons — WCAG 1.4.11 AA | 3:1 | Pass |
| Normal text — WCAG 1.4.6 AAA | 7:1 | Fail |
| Large text — WCAG 1.4.6 AAA | 4.5:1 | Pass |
Nearest passing colours
AAA (7:1)
How it looks with colour blindness
Simulated with the Machado et al. (2009) model at full severity.
- Aa
Protanopia (no red cones)
4.76:1
- Aa
Deuteranopia (no green cones)
4.32:1
- Aa
Tritanopia (no blue cones)
4.52:1
- Aa
Achromatopsia (no colour)
4.49:1
Try a different pair
Colours
Hex, rgb() or hsl(). Alpha is composited.
Preview
Large heading text
Normal body text at 14 px. The quick brown fox jumps over the lazy dog.
Colour-blindness preview
Simulated with Machado et al. (2009), full severity.
- AaProtanopia (no red cones)4.76:1
- AaDeuteranopia (no green cones)4.32:1
- AaTritanopia (no blue cones)4.52:1
- AaAchromatopsia (no colour)4.49:1
Contrast ratio
4.51:1
| Check | Criterion | Needs | Result |
|---|---|---|---|
| Normal text | 1.4.3 AA | 4.5:1 | Pass |
| Large text | 1.4.3 AA | 3:1 | Pass |
| UI components & graphics | 1.4.11 AA | 3:1 | Pass |
| Normal text | 1.4.6 AAA | 7:1 | Fail |
| Large text | 1.4.6 AAA | 4.5:1 | Pass |
Nearest passing colours
Same hue, lightness adjusted in OKLCH.
AA — 4.5:1
Already passes.
AAA — 7:1
Change text
#719bae · 7.00:1
Large text means at least 24 CSS px, or 18.66 CSS px bold. Ratios are truncated, never rounded, so 4.49:1 is shown as failing 4.5:1.
Questions about this pair
- Is #517a8d on #000000 accessible?
- Yes for WCAG 2.2 level AA: the contrast ratio is 4.51:1, above the 4.5:1 needed for normal text. It does not reach the 7:1 needed for AAA.
- What is the contrast ratio of #517a8d and #000000?
- 4.51:1, calculated with the WCAG 2.2 relative luminance formula. The ratio is truncated, not rounded, so it never shows a failing pair as passing.
- What colour passes AA on #000000?
- #719bae is the closest colour to #517a8d — same hue, adjusted lightness — that reaches 4.5:1 on #000000.
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