#51638F
Closest named color: Dusky Blue (#475F94). oklch(50.4% 0.074 266.7), rgb(81, 99, 143).
Aa
White text reads best on this color (5.94:1).
About this color
#51638F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 50%, its chroma 0.074 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Dusky Blue (#475F94), ΔE 0.021 away. White text reads best on it, at 5.94:1.
| Hue family | Blues |
| Lightness | medium-dark (50%) |
| Chroma | moderately saturated (0.074) |
| Temperature | cool |
| Nearest name | Dusky Blue (#475F94) |
| Black text | 3.53:1 |
| White text | 5.94:1 |
Values
| HEX | #51638F |
| RGB | rgb(81, 99, 143) |
| HSL | hsl(223, 28%, 44%) |
| OKLCH | oklch(50.4% 0.074 266.7) |
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 #51638F | 5.94:1 | AA | Lc -84.9 | Fine for body text |
| Black text on #51638F | 3.53:1 | AA large text | Lc 24.4 | Dividers and decoration only |
| #51638F text on white | 5.94:1 | AA | Lc 79.7 | Fine for body text |
| #51638F text on black | 3.53:1 | AA large text | Lc -22.1 | 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
#E7EAF1
oklch(93.7% 0.01 267.4)
-
Step 200
200
#D3D9E7
oklch(88.5% 0.02 267.3)
-
Step 300
300
#B6C1D9
oklch(81% 0.036 265.9)
-
Step 400
400
#90A0C5
oklch(70.6% 0.057 266.6)
-
Step 500
500
#7589B6
oklch(63.2% 0.072 265.8)
-
Step 600
600
#5E72A2
oklch(55.6% 0.079 266.5)
-
Step 700
700 (this color)
#51638F
oklch(50.4% 0.074 266.7)
-
Step 800
800
#404E71
oklch(42.7% 0.061 267.1)
-
Step 900
900
#36415B
oklch(37.7% 0.047 266.5)
-
Step 950
950
#202635
oklch(27% 0.029 267.5)
#51638F 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) | #546791 | 0.013 |
| Deuteranopia (no green cones) | #4D618E | 0.008 |
| Tritanopia (no blue cones) | #3C6C73 | 0.065 |
| Achromatopsia (no color) | #646464 | 0.074 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51638F
#51638F
oklch(50.4% 0.074 266.7)
- #77612F
#77612F
oklch(50.3% 0.074 85.8)
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 #51638F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusky Blue #475F94 ΔE 0.021
- Denim #3B638C ΔE 0.027
- Denim Blue #3B5B92 ΔE 0.039
- Muted Blue #3B719F ΔE 0.045
- Dusk #4E5481 ΔE 0.045
- Dusty Grape #545775 ΔE 0.047
- Metallic Blue #4F738E ΔE 0.048
- French Blue #436BAD ΔE 0.049
Use #51638F 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.