#51668F
Closest named color: Dusky Blue (#475F94). oklch(51.1% 0.07 263.2), rgb(81, 102, 143).
Aa
White text reads best on this color (5.75:1).
About this color
#51668F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.070 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Dusky Blue (#475F94), ΔE 0.028 away. White text reads best on it, at 5.75:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.070) |
| Temperature | cool |
| Nearest name | Dusky Blue (#475F94) |
| Black text | 3.64:1 |
| White text | 5.75:1 |
Values
| HEX | #51668F |
| RGB | rgb(81, 102, 143) |
| HSL | hsl(220, 28%, 44%) |
| OKLCH | oklch(51.1% 0.07 263.2) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #51668F | 5.75:1 | AA | Lc -84.0 | Fine for body text |
| Black text on #51668F | 3.64:1 | AA large text | Lc 25.3 | Dividers and decoration only |
| #51668F text on white | 5.75:1 | AA | Lc 78.8 | Fine for body text |
| #51668F text on black | 3.64:1 | AA large text | Lc -23.0 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 700.
-
Step 50
50
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E6EAF1
oklch(93.6% 0.01 261.8)
-
Step 200
200
#D3D9E6
oklch(88.5% 0.019 266)
-
Step 300
300
#B5C1D7
oklch(80.9% 0.034 262.7)
-
Step 400
400
#8FA1C3
oklch(70.7% 0.054 263.1)
-
Step 500
500
#738AB4
oklch(63.2% 0.069 262.2)
-
Step 600
600
#5C73A0
oklch(55.6% 0.076 263.3)
-
Step 700
700 (this color)
#51668F
oklch(51.1% 0.07 263.2)
-
Step 800
800
#3E4F6F
oklch(42.7% 0.058 262.6)
-
Step 900
900
#35425A
oklch(37.8% 0.045 262.4)
-
Step 950
950
#1F2635
oklch(26.9% 0.03 265.1)
#51668F with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #576991 | 0.013 |
| Deuteranopia (no green cones) | #51638E | 0.009 |
| Tritanopia (no blue cones) | #3B6F74 | 0.064 |
| Achromatopsia (no color) | #666666 | 0.070 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51668F
#51668F
oklch(51.1% 0.07 263.2)
- #7A6334
#7A6334
oklch(51.2% 0.071 83.8)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #51668F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusky Blue #475F94 ΔE 0.028
- Denim #3B638C ΔE 0.029
- Metallic Blue #4F738E ΔE 0.039
- Muted Blue #3B719F ΔE 0.039
- Dull Blue #49759C ΔE 0.043
- Denim Blue #3B5B92 ΔE 0.046
- Slate #516572 ΔE 0.047
- French Blue #436BAD ΔE 0.048
Use #51668F in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.