#51578F
Closest named color: Twilight (#4E518B). oklch(47.7% 0.09 277.8), rgb(81, 87, 143).
Aa
White text reads best on this color (6.75:1).
About this color
#51578F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 48%, its chroma 0.090 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.018 away. White text reads best on it, at 6.75:1.
| Hue family | Blues |
| Lightness | medium-dark (48%) |
| Chroma | moderately saturated (0.090) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 3.10:1 |
| White text | 6.75:1 |
Values
| HEX | #51578F |
| RGB | rgb(81, 87, 143) |
| HSL | hsl(234, 28%, 44%) |
| OKLCH | oklch(47.7% 0.09 277.8) |
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 #51578F | 6.75:1 | AA | Lc -88.2 | Fine for body text |
| Black text on #51578F | 3.10:1 | AA large text | Lc 20.8 | Dividers and decoration only |
| #51578F text on white | 6.75:1 | AA | Lc 83.2 | Fine for body text |
| #51578F text on black | 3.10:1 | AA large text | Lc -18.7 | 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
#E7E9F2
oklch(93.5% 0.012 276.1)
-
Step 200
200
#D5D8EA
oklch(88.5% 0.025 278.3)
-
Step 300
300
#B9BFDD
oklch(81% 0.043 276.5)
-
Step 400
400
#969DCC
oklch(70.7% 0.069 277.9)
-
Step 500
500
#7C84BF
oklch(63% 0.089 277.6)
-
Step 600
600
#666DAB
oklch(55.6% 0.096 277.9)
-
Step 700
700 (this color)
#51578F
oklch(47.7% 0.09 277.8)
-
Step 800
800
#454A77
oklch(42.6% 0.075 277.9)
-
Step 900
900
#3A3E60
oklch(37.6% 0.058 278.1)
-
Step 950
950
#222538
oklch(27.1% 0.036 276.8)
#51578F 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) | #435E91 | 0.025 |
| Deuteranopia (no green cones) | #3F598E | 0.024 |
| Tritanopia (no blue cones) | #3D626C | 0.079 |
| Achromatopsia (no color) | #5B5B5B | 0.090 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51578F
#51578F
oklch(47.7% 0.09 277.8)
- #6B5D14
#6B5D14
oklch(47.8% 0.09 97.7)
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 #51578F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.018
- Dusk #4E5481 ΔE 0.024
- Dusky Blue #475F94 ΔE 0.024
- Denim Blue #3B5B92 ΔE 0.029
- Dusty Grape #545775 ΔE 0.043
- Denim #3B638C ΔE 0.043
- Light Navy Blue #2E5A88 ΔE 0.045
- YInMn Blue #415A77 ΔE 0.049
Use #51578F 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.